Solving problems in a business setting is an important part of the Lean methodology. Using Lean strategies, a company can better identify what problems exist, pinpoint the root causes, and come up with the right solutions to get the best results. Learning about how to effectively use Lean problem-solving techniques can help any business to improve and become more efficient.
Lean Problem-Solving Process
When working to make improvements in any business setting, it is important to start by identifying problems or potential problems. Solving existing issues is a great way to eliminate waste and improve efficiency very quickly. For many businesses, this is the ideal with to create a competitive edge that will help you to succeed.
When using the lean problem-solving techniques, you will go through a series of steps to get the results that are needed. The steps in the Lean problem-solving process are as follows:
- Identify the Problem – The first thing to do is identify what the actual problem is. This should be as specific as possible and include as many details and other information as is available.
- Break it Down – Breaking the problem down into different steps or parts is critical. This will make it possible to develop the right solutions for each aspect of the problem and help get things running as they should.
- Establish Targets – It is difficult to solve a problem if you don’t know what a working system should look like. Establishing target goals for the system you are working on will help guide you through the rest of the process.
- Look for the Root Cause – No problem can be truly solved without knowing what the root cause is. Keep asking questions about the issue at hand until you discover what is truly causing the issues. This can often be done using the ‘Five Whys’ technique, where you keep asking why something is happening until you reach the root cause.
- Propose Countermeasures – Next, come up with ways that you can address the root cause. This could be one or more different actions that are designed specifically to deal with this issue.
- Implement Countermeasures – Take the countermeasures that are proposed in the previous step and begin testing them. Ideally this can be done in a small test segment, but if needed it can be done in a full production environment. If a solution seems to work in a small system, expand it out to make sure the results scale up as expected.
- Test the Results – Analyze the results by comparing the situation where the problem was found against your target results. If you are able to accomplish the goals identified as your target results, the problem-solving countermeasures are successful. If not, move back to proposing additional countermeasures to get the results you need.
- Standardize – Once you have found a proven way to address the problem at hand, it is time to roll it out to the entire environment. Establishing new processes and procedures that will be followed by everyone in the facility is the last step in the problem-solving process.
Include All Impacted Parties
When going through the Lean problem-solving process it is important to consult with all the parties that are impacted by the problem at hand. It is quite rare that one person will be able to find the best possible solution to a problem, especially if they aren’t the ones who are directly impacted by the issue. Part of the Lean methodology is to work with various teams to come up with the best way of doing things. If you are facing a problem that needs a solution, you will want to include people from various groups such as:
- Front Line Employees – These are typically the people who will deal with the problem on a regular basis. Nobody will have greater insights into the root cause, and potential solutions, than these employees. Having one or more people from this level helping to solve a problem is critical.
- Supervisor – A supervisor or department manager will be able to provide additional insights into how the problem is impacting the business. They will also be the ones to help coordinate the implementation of any potential solutions so they should be involved.
- Appropriate Management – If a problem, or the expected solutions, will require upper level management approval, someone from that team should be included in the process. It is easier to have someone from the leadership partnering with you from the beginning than to try to bring them up to speed for approval down the road.
- Customers – When appropriate, having a customer available to discuss the problem can be very helpful. Customers are sometimes the ones who have the most information about the symptoms of the problem, which can make them very helpful.
Solving problems using Lean methodologies is a great way to help improve efficiency and eliminate waste in any workplace. Having an established process in place will allow you to quickly identify and solve a wide-range of problems in any environment.
To achieve success with Kaizen – the Japanese philosophy of change for the better – it’s beneficial to adopt some of the tools in the continuous improvement toolbox.
A kaizen newspaper is a document that lists current ideas, problems, solutions, and responsible parties. The newspaper is usually in spreadsheet or chart format and it is posted so everyone can see it. The document also indicates which phase of the PDCA cycle an idea is in. The goal is to help keep people on track and prevent ideas from falling through the cracks.
Some workplaces create a larger visual board where kaizen ideas are posted. Alternatively, this board can highlight kaizen successes, sort of like a kaizen “wall of fame.” Seeing these successes can do several beneficial things. It can motivate employees to find new ways to improve, it can make employees whose ideas were successful feel appreciated, and it can help everyone in the organization track progress over time. This tool can serve as a record of continuous improvement.
A suggestion box is a traditional method for soliciting ideas from employees, and some workplaces that use kaizen employ suggestion boxes – either physical or electronic – for submitting ideas. These boxes can be useful, but it is important for a workplace to make sure someone is checking the box regularly and responding to ideas quickly. It’s easy for suggestion boxes to get neglected, and when that happens employees may feel their ideas aren’t taken seriously. All ideas should receive a response.
A quality circle is an activity that engages employees in improvement efforts regularly. Quality circles are small groups that have been used frequently in Japan. These groups often contain employees who perform similar functions in the company and they meet regularly to solve problems and discuss quality, cost, delivery, and other important topics. These circles can help people learn how kaizen works and reinforce the importance of paying attention to improvement possibilities. Implementing kaizen takes work. People need to be educated about kaizen and the role it will play in the workplace. Events may need to take place to demonstrate how improvement processes such as the SDCA and PDCA cycles work. Quality circles or other tools may be instituted and time may be scheduled for daily kaizen. Management, supervisors, and employees all need to know their roles and feel that their ideas are respected. At first, the improvements may seem small, but as time goes by, organizations using kaizen will likely see notable gains in the way processes work. Ultimately, this can lead to happier customers, which means a more successful business.
Lean manufacturing aims to eliminate wastes and improve productivity, primarily by operating on a pull system known as just-in-time (JIT) production. The JIT method is opposite to push systems on the spectrum of supply chain management and can often be the barrier for a company going Lean.
In a push system, production is scheduled to meet the forecasted rate of demand. Also known as mass production, the push method has been around for centuries and while there are instances in which it might be beneficial, this kind of system can easily become a wasteful strategy. There are no limits on WIP and products are processed in large batches before moved down the production line or into storage. An inaccurate prediction can have a major impact on inventory levels or cycle times, and many organizations find themselves producing excessive inventory,
Pull systems on the other hand, are dependent on actual customer demand. The idea is that nothing is made, and no process is started without a submitted order from the customer. It’s virtually impossible for an organization to order materials and plan a strict pull system, which is where Heijunka comes in. Developed as part of the Toyota Production System, Heijunka translates to mean production leveling. By leveling either by volume or type, you can develop a system that not only works for your specific product and facility but sets your organization up for Lean success.
JIT and Kanban
Arguably the most important tool in operating this kind of production method is Kanban, a tool also developed by the Toyota Motor Corporation. Kanban uses visual cues, like cards or bins, to trigger an action further down the production line. Processes (like value-added activities) only occur when the bin or card is received, and operators ensure only quality products are moving to the next stage. Kanban can be tailored to fit the needs of an organization, some companies just starting out may go with a 1-card system while others may choose to use a more sophisticated electronic system with barcodes and scanners.
Other tools you may want to be familiar with in a Kanban system are:
- Kanban Boards: A simple visual representation of work in process. A basic board would usually be split into three different stages of “To Do,” “in Progress,” and “Completed.” People can quickly track orders as they move through the process and office departments can even utilize them for administrative purposes.
- Other visual cues: Bins and cards don’t need to be the only visual trigger! Think outside of the box and use something like color-coded floor markings to indicate when something may need to be produced or ordered.
A system using JIT manufacturing and following the principles of Lean with a pull system will find their system is much more flexible. If demand fluctuates or market conditions shift unexpectedly, you will have an easier time adapting production accordingly. It ensures production is only happening effectively eliminating overproduction and over-processing, which can hide defects and cause a whole bevy of other wastes.
Once you implement the 5S model in your place of business, you will see the improvements very quickly. By the time you reach the fifth and final phase, your space should be cleaned and organized and standardized procedures should be developed. But the key to key to long term success is simple – diligence. You need to sustain these results and your progress in order to have a successful 5S program.
Here are some great techniques to keep your staff motivated:
Assign the time to do it.
Give your staff the time to do the steps correctly. For example, designate the fifteen minutes before lunch and shift end as Shine time. During this time, their main focus could be cleaning and organizing according to their checklists.
Start from the top.
Your whole organization must be on board if 5S is going to work in the long run. If your employees see that management is not following the steps, do you think that they will continue to do it?
Create a reward system.
Have friendly competitions between departments each month and reward the winner. Buy them lunch, let them go early one day, or give them priority parking. It doesn’t have to break the bank; you just want to show them your appreciation for a job well done.
Get everyone involved.
Form a committee made up of employees and supervisors of different departments. Their job will be to oversee the implementation of 5S for a fixed period, maybe six months, and then you can rotate in new members. Listen to employee feedback and take their suggestions into serious consideration.
Let them see it.
Posters, banners and newsletters can be a constant reminder of the importance of 5S. Consider posting pictures of the space right after the third step, Shine. This will serve as an example of how it should look at the end of each work day.
Train new employees.
When a worker joins your 5S organization, have current employees carry out their training on the system. This will not only ensure your efforts will be carried over to new workers, but it gives existing employees the opportunity to evaluate their own knowledge and ask questions.
A common concern with this methodology is that the new 5S efforts won’t have the intended results. It’s important to not be discouraged If the 5S audits are coming back and they’re not stellar. This is a problem many organizations face, but a problem that can be fixed. Most issues can be traced back to three contributing factors: inadequate employee training, lack of time, or lack of requested feedback. If you are unsatisfied with your 5S program, evaluate each of these areas and identify where you can make improvements.
Going Lean means implementing a culture of continuous improvement, and constantly try to identify and eliminate the 8 types of waste: defects, waiting time, extra motion, excess inventory, overproduction, extra processing, unnecessary transportation, and unutilized talents. It’s critical in Lean to evaluate all areas in a facility for waste, even less obvious ones. One area you could save time and resources by using the right tools is your toolbox. Often times a box or bucket of tools will lead to a messy, and ultimately inefficient, workspace. There are supplies designed to straighten up your tool area and get back that lost valuable production time; here a few to consider trying out:
Pegboards: Hanging up tools and storing them out in the open will allow employees to quickly grab what the need and replacing a bulky toolbox with wall storage is a great space saver. Different materials and different sizes gives you the options to set up a tool storage area suiting your facility perfect. Employees will be able to quickly identify a tool’s “home” and will be able to find tools in just a few moments. Having your tools openly displayed will cut down the time of employees rummaging in a toolbox looking for a tool, and it will be easier to identify missing or misplaced tools at the end of a shift. Pegboards will ensure tools are stored properly while also helping to prevent and loss of tools. This can be a huge time saver if an employee doesn’t have to constantly track down tools.
Tool Outline Vinyl: Also called shadow board tape, this type of adhesive are custom cut shapes letting workers know the tool’s “home”. You can utilize this tape on pegboards, cabinets, drawers, toolboxes, and other consider using shadow board tape to create a guide for where the tools go. Set up a logical order to save even more time: store screwdrivers next to each other, have an area specifically for hammers, etc. You’ll eliminate waste of people trying to find the home of a specific tool and in the case of loss or theft, you will be able know exactly what type of tool is missing.
Tool Foam Organizer: Keep using your existing toolbox and give it an organizational makeover with customizable foam. Installing a foam organizer gives you the option to cut out specific shapes, choose contrasting colors to highlight missing tools, and more. Like the tool vinyl, identifying tools will be much easier, and the foam adds an extra layer of protection to fragile or expensive tools. This strategy, similar to the others, requires some assembly but the options really are endless.
Whatever option you decide to go with, all three are highly effective in improving efficiency. It’s important to remember to constantly evaluate the success of your efforts and continue to make improvements.
Understanding the Seven forms of Waste
If you are looking into implementing lean six sigma principles, the first thing you will need to do is to look at the seven forms of waste. Having a good understanding of what each of them are, and how they can be addressed in your facility, will help to ensure you are able to operate more efficiently.
When companies don’t take the time to really understand these seven forms of waste, they will end up losing focus over time. In the end, this can leave a facility in the same state it was in before, or sometimes even worse. With this in mind, take a moment to read about each of the seven forms of waste that are identified in the lean six sigma methodology.
Reviewing the Seven forms of Waste
When a facility produces too much of a product, it is a form of waste. Even if the product does eventually sell, it causes certain types of waste. For example, if you have too much of a product, it needs to be stored in a warehouse, which is wasting space. In addition, if the product isn’t selling well, you may have to sell it at a discount, which reduces profits.
2. Excess Motion
Motion is necessary for the creation of products, but all too often things are moved unnecessarily, which is wasteful. This can happen when machines are not positioned efficiently so an item has to be transported long distances to get where it is gone. Too often, the item then has to come back the other way to finish a process.
Minimizing excess motion is a great way to reduce waste, since it won’t require resources to complete that motion. Another example of this is if someone is taking an inefficient route to where they need to go. Some facilities have even used colored floor marking tape to identify paths based on which product is being moved. The product simply follows the path along through the process so everyone knows the most efficient way to get to the next step.
Another of the seven forms of waste is waiting. This can happen when work is not properly planned, so people working on one machine have to wait around for work from a previous station. Working with the work schedules of employees, you can often minimize the waiting to eliminate this type of waste.
People standing around doing nothing is just one form of waiting, however. If a machine has to wait for additional parts or resources, that is also wasteful. This is why proper inventory control is an important way to reduce waiting.
4. Unnecessary Processing
Many companies make improvements to products just for the sake of improving them. If customers don’t want or need the improvement, than this is a type of waste. When customers don’t demand a change, they won’t be willing to pay for it.
If you find that a specific feature of a product is not something that your customers want, than it should be eliminated to avoid unnecessary processing.
When items are moved around unnecessarily, it is wasteful. For example, some facilities will store a product in a warehouse for some time. If it sits for too long, they may move it to another warehouse or another location within the warehouse. This transportation does not provide any value, and actually wastes the resources of the people and machines that have to move it.
In addition, whenever there is transportation occurring, there is a risk of damaging the products. If an item is dropped, it will have to be fixed or even remade. This is, of course, a significant waste.
6. Excess Inventory
Having excess inventory is one of the more common types of waste. This doesn’t just mean too many finished products, however, if you are storing a large amount of parts that are used for the creation of a product, that is also wasteful.
Ordering only what is needed for a specific order will help to ensure none of them go to waste. Having a system in place that will order more of each item when it is needed, and in a way that will ensure it shows up as close to the point where it is required as possible, will help to reduce inventory.
Whenever a product has a problem, it is very wasteful. Defective parts or products need to go back through to either be repaired or disposed of. Finding defects as soon as possible and identifying root causes of the problem so that it doesn’t happen again is essential to a lean workplace.
Even if it takes some time and resources to identify the causes of defects, it will be well worth the effort in the end. Over time, as the facility sees fewer and fewer defects it will be clear just how important eliminating this type of waste really is.
Always Review for Waste
Understanding the seven forms of waste in a lean facility is really just the beginning of an ongoing process. You need to make sure you are always on the lookout for any of these types of waste in the facility, and then put in the effort to have them eliminated.
At first, most facilities are able to find a lot of different wasteful things and make fast improvements. Over time, however, they can become more difficult to identify and smaller in nature. This is a good sign that the facility is beginning to operate more efficiently with less and less waste.
Poka Yoke Techniques to Help Eliminate Waste
If you haven’t heard of Poka Yoke before, you might think you’ve accidentally stumbled onto the wrong website and are about to read a writeup on a strange dance phenomenon. In actuality, Poka Yoke techniques are the strategies used by professionals in order to minimize defects or mistakes in an industrial manufacturing setting. Like many Techniques of our time, Poka Yoke can trace its origins back to the ‘Toyota Production System’, as described therein by Shigeo Shingo.
As an honorary (if not undermentioned) Lean technique, Poka Yoke helps to eliminate waste by ensuring that defective products don’t use up your materials, manpower, or production time; even a defect that can be re-worked, and therefor doesn’t result in material loss, wastes time and energy. In this blog post, we’re going to break down Poka Yoke and go into some specific ideas you can keep in mind to make your own implementation as effective as possible. Hopefully, it’ll help to kick-start your thinking about how you might work this valuable tool into your place of work.
Poka Yoke, literally translated, means to mistake proof a system. Before, however, different words were used and the concept was called “fool” or “idiot” proofing. While the more sensitive name is the one that was republished a million times over in training literature and Lean manuals, sometimes a nod to the original translation can be useful. That is to say, one of the most effective ways to implement Poka Yoke is to feign ignorance. Here’s what I mean:
The ‘Dummy’ Walk: Other people may have a more scientific name for this, though I refer to it as the dummy walk tongue in cheek. Really, you’re not pretending to be an imbecile or someone with a low IQ, what you’re trying to do is place yourself into the shoes of someone who is completely unfamiliar with your business.
Walk through an operation step by step, and think about, if you were someone with no experience in the industry, how you would know what to do. “But wait, my workers are trained,” I can hear you saying, “this would only be helpful if I never trained my workers in the first place!” The truth of the matter, however, is that accidents happen, people get tired, etc. Keep in mind that the end result of this technique isn’t necessarily to design an assembly line a toddler could operate, but in looking at production in such a way you will pick out the bigger problems rather quickly.
As an example, let’s say workers inspect and feed finished toy blocks into a chute to be packaged near the end of assembly. If you notice that every once in a while a defective block slips through, one Poka Yoke technique you could implement is a guarding device that is cut to only allow the correct pieces through.
The goal of a dummy walk is accomplished then by observing the process in the shoes of someone with no previous knowledge, identifying a potential problem, and then implementing a fix or failsafe to account for it.
Close Proximity: One Poka Yoke technique that is often overlooked is the importance of close proximity. This concept can be applied to a number of other strategies as well. Basically, the proximity rule with Poka Yoke means that it’s best practice to place any kind of control or defect-reducing mechanism as close to the process you’re trying to control as possible.
This is helpful for a number of reasons, but the big one is isolation. The closer a device is to the things it’s supposed to deal with, the more likely you are to interact with the intended factors and the intended factors only. In our example above, maybe there’s a final step after inspection where a final piece is affixed to the blocks. With this final piece, the blocks wouldn’t fit through the custom guard. Obviously, you wouldn’t want the defect guard on after that step or you would experience unwanted interaction between the Poka Yoke device and a stage of production.
Obviously, that’s an overtly obvious and silly example, but in the real world much more subtle activities or factors between a device and the issue its intended to fix may not be noticed until it’s too late; the last thing you want is to waste money on installing or implementing something that just has to be removed and done over again, yikes! If you’ve already got a few defects in your production cycle, the last place you want them showing up is in the measures meant to address those very problems!
The Factors of Any Good Poka Yoke Technique
In addition to proximity, there are several other factors that can quickly tell you if you’re implementing Poka Yoke in a way that is likely to be effective.
1. They’re natural. Poka Yoke devices should fit naturally into an already existing process; implements that deviate too much form what’s established can become to time consuming in and of themselves to be of net benefit to you.
2. They’re not complicated/expensive. Likewise, techniques or fixes that are overly complicated (hard to learn) or that cost a lot of money to implement can dramatically increase the time it takes for them to ‘pay off’ in decreased defect rates and time saved day to day. Try to boil any ideas you have down to their very simplest elements before implementing them.
You may even come up with a few rules of thumbs through your own trial and error, but hopefully these will help guide you a bit, at least when you’re starting out.
One of the closing thoughts I want to leave you with is that Poka Yoke can really be anywhere and be anything. Even when we talk about specific Poka Yoke ‘techniques’ the best advice I can give you is to let your own implementation be creativity-lead. Don’t know if someone’s done it before? Who cares! Your business is its own unique machine, treat it like one.
Implement Kaizen Continuous Improvement in 5 Steps or Less
Kaizen, the Japanese term underlying the concept of “continuous improvement,” continues to dominate work flow theory and the training that improvement professionals receive when they look for ways to bring their charges ‘to the next level’. Of course, the traditional tools and teachings of Kaizen are time-proven and ultimately brilliant in their own right, but there are undoubtedly other factors that can influence the effectiveness of Kaizen.
Today, I want to focus on five contextual factors that a workplace manager or Lean/Six Sigma professional can do to help improve the way they, well, improve! Contextual Kaizen involves bettering one’s self and one’s work environment to be better equipped to implement Kaizen in the first place. Some of these will pertain to very specific tasks or skills, while others are more about training your mind to view problems and improvement opportunities in a certain way. As with just about any piece of advice, these tips will work better when customized to your own operations, and some of them will be better suited for your business than others. Without further adieu, let’s jump right in!
Top 5 Tips to Make Kaizen Work for You
1. Don’t Do It All The Time, Just… Don’t
Confused yet? I’m actually talking about Kaizen itself, because one of the best ways to shut yourself off to new ideas, to get overwhelmed, or to get stuck into a solution or category of solutions that just isn’t working is to tunnel vision yourself into one pursuit. Creative industry professionals know that the best ideas usually don’t come from sitting at a desk thinking about the idea itself, they come from stimulating the brain in other ways.
While training and learning about Kaizen in a traditional sense are important, challenge yourself to completely get out of the house/office and dedicate some “outside time” to your continuous improvement efforts. The hardest part about this tip is that many people will disregard it as counter-intuitive, if you’ve got an issue that needs tackled, how is ignoring it going to help? And, really, I’m not telling you to ignore it, but to just try and draw inspiration from other things and places. Remember, the very first time a great idea was implemented, it had to be thought up. Sure, there were influences from previous iterations, but something truly innovative can’t be simply picked out of a book or online course. Find your golden acorn out in the open world.
2. Teach Others
When it does come down to the booksmarts, one of the absolute best ways you can crystallize LSS teachings in your own mind is by teaching them to others. For example, when I was in college I tutored a student who was struggling in our basic calculus class. When he started doing better on his tests, I wasn’t all that surprised, but then something even more interesting happened: I improved too. I went from A’s and B’s to straight A’s (and several 100% grades) for the rest of the semester!
Teaching others the skills you learn forces you to fully understand them. You can’t just breeze over things and think “yeah, yeah, I get it,” you have to really know what you’re talking about if you’re going to explain the ins and outs of it to others. In Kaizen, a great way to do this is to workshop with your employees and go through various hypothetical (or real) improvement scenarios. By doing this, you’re likely to not only improve your own knowledge but also help get people on board with your continuous improvement efforts as they’ll better understand both the means and objectives.
3. Find Other People’s Stuff That You Love, Document It
Not every single idea is going to be a game changer, but marginal improvements can be made in many aspects of your business just by simply observing what others are doing. This could be your direct competition, or companies in completely unrelated industries that are doing something you like.
When you’re at the store and come across packaging that catches your eye, slogan ideas that stick in your head, or see employees in another warehouse doing something that you think would work well in your own, document it. Take pictures and notes using some combination of a notepad/phone/camera as your current situation allows, then take these ideas back to the office and see if any of them could work for you.
4. Become A Entertaining Presenter
No really, become the Tony Robbins of the boardroom; get people pumped about your ideas! Continuous improvement means continuous change, and change can be intimidating. While I’ve done plenty of articles on compliance amongst improvement efforts, a stand out factor is “selling” people on what you want them to do. While step number 2 (Teaching Others) is one way to do this, you probably won’t have time to teach everyone everything, after all, they do have other jobs to do!
Instead, take public speaking and even art classes, and learn to draw and illustrate your ideas effectively while talking about them at the same time. Continuity of ideas and confidence both inspire people to follow you, and these small things you can teach yourself will help you to exude both of those.
5. Improve Yourself First
You’ve probably noticed that many of these ideas ties into “self-improvement,” and that’s for good reason. One of the hallmarks of a true Kaizen expert is that they’re always evolving and keeping up with the latest trends and knowledge. In order to stay relevant and knowledgable, try your best to make a conscious effort to always improve yourself, much in the same way you want to improve a company.
Read daily blogs, subscribe to useful twitter feeds, join groups on LinkedIn that discuss continuous improvement strategies regularly, etc. Then go old school and buy books, CDs, tapes (wait, do those even still exist?), and whatever else you can get your hands on.
When it comes to Kaizen, don’t feel selfish putting yourself first – your ideas, and thus your workforce, bottom line, etc., will benefit from it greatly.
Making Improvements with Six Sigma Root Cause Analysis
When things aren’t going the way they should, it can often be quite difficult to identify what is actually causing the problem. Despite the fact that it can take a lot of work, root cause analysis is extremely important because of the fact that it will allow you to not just cover up issues, but actually address them directly.
In many cases, this will allow you to make significant long term improvements to your facility. With that in mind, all facilities should have a method of digging into problems to discover the root cause. For a growing number of facilities, this methodology comes right from their existing Six Sigma strategies.
What is the Six Sigma Root Cause Analysis Strategy?
The Six Sigma root cause analysis strategy is often known simply as the “Five Whys.” As you might expect, it gets this name because of the fact that it encourages those working on problems to ask “why?” until they get to the root cause of the problem.
In reality, you may have to ask yourself (or your team) why only once or twice or far more than five times. The important thing is to make sure you are asking the right questions and that you don’t stop until you get to the actual root cause of the problem.
Before you ask yourself ‘why’ at all, however, you need to clearly define the problem. The Six Sigma standard suggests that you write it out so that you and the entire team have a single point of focus when working on the issues. This will help you to avoid getting distracted when performing this root cause analysis.
To get a concrete idea of how this could work in a normal, everyday situation, follow this simple example. If you are driving home and your check engine light came on, you might run through a Six Sigma root cause analysis to figure it out. First, you define the problem statement, which might be, “Your vehicle is operating, but the check engine light has come on.” You would then begin asking why? For example:
- Q) Why did the check engine light come on?
o A) Because the serpentine belt came off. *You can confirm this by looking under the hood or seeing if other systems that rely on this belt are impacted.
If you determine that this is not the root cause of your problem, you will move on to the next why:
- Q)What is another reason why the check engine light came on?
o Because I have not changed the oil in eight months. *Again, confirm this by checking the oil levels or taking it to a mechanic.
If you find that this is the cause, you will still need to continue asking why, since the oil not being changed is not the root cause:
- Q) Why wasn’t the oil changed on time?
o Because I forgot to schedule the oil change.
- Why did I forget to schedule the oil change?
o Because I stopped using my calendar app on my phone
You now know that the root cause to your engine light is actually the poor organizational skills and a failure to use the proper tools to help prevent these types of things. As you can see, by getting to the root cause of this issue, you actually likely avoided a variety of other problems in the future (related to the root cause of poor scheduling and organization).
Of course, you will have to take steps to fix the problem, but once you have identified the root cause, that won’t be difficult at all.
Keeps the Focus
One of the biggest benefits of the Six Sigma root cause analysis system is that it helps to ensure that everyone working on a problem stays very focused. It can be tempting for many people to get off topic and start looking into potential issues that aren’t related to the actual problem at hand.
While this can be beneficial for discovering other issues, a root cause analysis session is not the right time for it. By continuing to ask ‘why’ based questions, it allows you to keep moving forward in the investigation.
Easier to Identify the Actual Root Cause
Another major advantage to this system is that it is much easier to know when you have reached the actual root cause. When you can’t think of any more ‘why’ questions that make sense to ask, that almost certainly means that you’ve reached the root cause.
Some people may be tempted to keep finding and asking these questions (as you can always ask why) but when it is clear that all the questions being asked aren’t actually helping to drive toward a root cause, the process is over. You can then find where the questions ended, and that is the root cause.
Finding the Solution
With the Six Sigma root cause analysis strategy you are not only able to find the actual root cause much more effectively, but the solution to the problem is often built right in. Once you see where the root cause is, you can often go back and look at the answers to the previous questions to come up with ideas on how to address that root cause.
In a way, the whole process of finding the actual cause of issues is actually going to be preparing you for the problem resolution as well. This will allow the problem analysis and investigation to go much more quickly, while also being more effective.
For example, if there is a safety issue where there are frequently accidents or near misses in an area where there are frequently people walking as well as high-low’s driving, you can use this method to ask several why questions, to which the answer may lead to the fact that there is no easily identifiable difference between where people should be walking and where vehicles should be driving.
Once you get to this conclusion, you can quickly realize that adding floor marking tape that clearly distinguishes where vehicles need to drive will solve the problem. You can also determine whether or not it is necessary to use color coding for this, or even using floor marking shapes for further benefits.
The bottom line with the Six Sigma root cause analysis strategy is that it will help you to more quickly determine what exactly is causing the problem, while at the same time coming up with a solution. It is well structured and can be effective for nearly any type of problem imaginable.
Causation vs. Correlation in the Lean Business World
For anyone who’s had to sit through a year of high school statistics, and even for many of those who haven’t, you’re familiar with the phrase “correlation does not equal causation.” While many of us nodded our heads in agreement after some simple illustration, the impact of not intimately understanding this concept in the business world can be catastrophic.
I bring this up now because the topic recently arose on a favorite LinkedIn group. Several commenters offered up some examples and/or simply voiced their agreement, and I found this troubling. Troubling not because it was incorrect, but because you can see misunderstanding of the concept clearly negatively influencing businesses on a daily basis, despite the fact that everyone already apparently ‘knows it’ and agrees with it.
Before we get further into it, we should do a quick refresher of what the words and phrase mean. I went into this article with the assumption that everyone’s likely familiar with the concept already, but you know what they say happens when you assume…
Causation Does Not Equal Correlation
Let’s do a quick breakdown:
Causation: One factor or event leading to another; this could illustrate dependence – as in factor A is necessary for factor B to happen – or simply be one of the ways in which something happen (even without factor A, factors C, D, E, or F could all lead to factor B independently). The main takeaway is that one thing is happening because of another.
Correlation: Correlation is a simpler concept, and can be summed up as “a pattern between” two things. If two things are correlated, there are trends within each happening at the same time. Correlation can be positive (two things increasing or decreasing at the same time) or it can be negative, also called inverse (in which one item increases while the other decreases, and vice versa).
The meaning of the main phrase in question today is simply that while things might be correlated, or appear to move in similar or inverse ways with relation to one another, this does not mean a change in either is responsible for or a result of changes in the other.
It’s quite easy to illustrate this, and a few great examples are shown in the article linked in the original LinkedIn post. One, which graphs the US murder rate over the past few years vs. the market share of Internet Explorer as an internet browser, makes a particularly good case for a correlation between two things doesn’t necessarily point to a causal relationship.
Indeed, the chart shows clearly that murder rates have gone down while Internet Explorer usage has as well. Obviously, IE probably isn’t making people so upset as to drive them to murder (it’s not that bad), but the correlation exists nonetheless. Other funny examples in the article include number of pirates vs. global temperature and sheet entanglement deaths per year vs. cheese consumption (both of which show positive correlation).
The implications of this become more sinister when correlations that aren’t so obviously ridiculous are shown side by side. News stations, bias reports, and more could – and do – easily make it appear that one thing is causing another, even when that hasn’t been proven to be the case.
In The Workplace
“That’s all well and good,” you’re thinking, “but what the heck does it have to do with ME?!” Well, the simple fact is that Lean/Six Sigma thinking focuses on improvement, and one of the only ways we can improve a situation is by knowing what’s causing it in the first place. While working to identify root causes, it’s easy to ‘bridge’ gaps in our evidence with assumptions, and this is where we can run into trouble; after all, addressing one issue won’t help unless it really is (one of) the ones affecting the other.
Let’s say you’ve mapped out operations and notice a particularly slow station. After some investigation, you see that it turns out that all of the days with the biggest delays are when an employee named John is working. Sure enough, every day John is on that station, productivity slumps.
In response, you don’t tell John what’s going on but do enroll him in some extra training on his work. A couple weeks later, nothing’s improved. Now you bring John into your office to have a talk. As you’re about to get to an ultimatum, John speaks up and offers what is probably the real cause of your troubles: A supervisor on the floor shares a hobby with John, they both enjoy boating, and every time John’s on the workfloor the floor manager comes over and has a chat with him about boating, asking questions about building his new boat, etc. Inevitably, productivity slumps as John has a period where he can’t focus on his work.
Whether John was just a lazy worker or he had a distracting supervisor slowing him down, your original data would have shown up the same. In the end, however, it becomes apparent that despite the correlation, John is not actually the cause of slowdowns on the days he works, and your correctional efforts need to be focused elsewhere (on that chatty floor manager, to be precise!).
This is just one very specific and clear-cut example of how this concept can lead to problems in workplace ‘improvement’. In real life scenarios, the relationships can be much more complex, and getting to the bottom of the “root cause” of a problem, a common strategy in Lean, can be more difficult that in this example.
Don’t Mistake Correlation for Causation
That said, there are a few important things you can do to help reduce false positives and ensure that you don’t mistake correlation for causation.
Don’t Assume: When it comes to digging down and figuring out how to improve your business, preconceived notions kill progress. Remain open and try not to weigh in or even think about solutions until you have your data.
Be Critical: Even once the findings are in, ask yourself what more you can do; are there other areas to investigate? Are you sure you’ve identified the right cause? Is there actually more than one?
Talk To People: From afar, it can be hard to move from an overall view to a specific, insightful one. Always work with your employees to get the information you need. Remember, a simple conversation with John would have set our imaginary business owner on the right path sooner. In the end, it’s all about saving you time and money, so use the tools available to you to track down the right leads as early as possible.