CI Tools

What is 5 Why analysis? How to use 5 Why and Fishbone diagram for root cause analysis.

One of my favorite tools for root cause analysis is 5 Why.  I like it because it is simple, and you can use it anywhere, and for any situation.  You don’t need to do complicated analysis, take notes or draw anything, you only need to keep your brain asking why until you find the root cause for the problem.  It is also very helpful to see the relationship between different causes. 

This tool is simple but requires practice.  The number of times you ask why depends on each particular situation; five it is not a number written on stone.  If you stop asking why too soon, you will end up far away from the real root cause and asking too many times result in complaints or non-sense answers.

Most of the time the root cause of a problem falls into one of these categories

  1. No standard or inadequate standard
  2. Not following the standard
  3. Inadequate system or equipment

These are the steps to do a Five Why analysis.

  1. Define the problem.
  2. Start describing the problem using all details from the problem definition.
  3. Ask why the problem happens, this is the answer to your first why.
  4. If the answer does not identify the root cause, ask why again.  This is the answer to this why.
  5. Keep repeating the fourth step until you identify the root cause.

My last post was about fishbone, another tool that I used very often.  I like to use it to explore all possible causes because it helps to force people to think beyond the obvious reasons.  Once you complete the cause and effect diagram, you should end up with one or two causes.  At this point, you can use the 5 Whys to drill down the root causes.  

The fishbone I used is from an analysis completed in a food manufacturing plant.  We were looking for the cause of getting excess oil in the body of cans containing oil products.  The fishbone analysis results in two possible causes, both of them related to the equipment used to wash the cans.  The causes were the alignment of the detergent nozzles and the quantity of soap dispensed.  We used the 5 Whys to determine the root cause of each, and we find that the reason was that there was no standard for the setting of the equipment.

Most of the time, when a problem happens, the first thing you see is a symptom.  In this example, the symptom was oily cans.  Without root cause analysis, most probably we would stop at insufficient training, but with fishbone and 5 Why we were able to drill down to the ugly truth, a standard was never established.

Now you have two simple and effective tools to use to find the root cause of a problem.  Practice PDCA and use these tools for RCA, you will see the difference between traditional and lean problem-solving.

CI Tools

Do you really want to go back to normal? Business as usual, will not going to cut it anymore.

These days you can hear the phrase when we go back to normal, dozens of times a day.  We all want to return to our normal lives, right?

As a lean practitioner, I believe that each event is a learning opportunity, the coronavirus pandemic is no different.  During these slower days, there is time to learn new things and plan for the future.  Lean is all about learning, experimenting, and adapting.  That is just what everybody needs to learn now.  Every day I read about how people are adapting to the new normal, and many are using lean or continuous improvement thinking without knowing it.  For me, at this moment, Lean style problem solving is the on-demand skill.

I am not the only one that thinks that way.  Last year, the Indiana Department of Workforce Development (DWD), published Indiana’s Employability Skills Benchmarks.  It describes a set of 18 workplace skills recommended for success in today’s competitive workforce.  One of the skills identified in the learning strategies category is problem-solving.  

The way each business adapts the operation to comply with the CDC guidelines is unique.   The solutions are not one-size-fits-all, and on top of that, those guidelines change as they gathered more information.   Learning how to use a systematic process like PDCA and apply lean thinking is critical to identify and implement the new operational guidelines for your business.  

This situation catches most people without the skills to learn and adapt, but it is never late to start.  You are on time to start using lean thinking to approach the current challenges.  With practice, you can build that muscle memory that will guide you through times like this.  The new normal then should be something better than before the coronavirus pandemic.  It is like when you create the future state value-stream-map, imagine a better and stronger business and plan how to make it happen!  Many will go back to business as usual, your competitive advantage will be your new way to do business.

Better Process Solutions can help you to start designing your new processes, get in touch!

CI 101

Why Plan is critical for the success of your PDCA?

Monday, I talked about what the PDCA cycle is. Today I want to highlight how critical the step Plan is.

PDCA Cycle

Many times, while analyzing a problem, we don’t spend enough time understanding it. Instead of looking for the root cause of the problem, we start developing theories to correct the symptoms. If we create a plan to test possible solutions to the wrong problem, then the plan is doomed to fail.

The most important part of the PDCA cycle is understanding the problem. Get the background of the current situation. Even when you think you know the process, ask why it exists. Check the capability, expected outcomes, and actual performance. What value does it provide to the customer? Research regarding any possible risks, policies or regulations that can affect efficiency.


You must spend time observing what is going on. Go to gemba, where the action happens. Observe for as long as you can, and take notes to compare against all the data. You cannot have the whole story if you don’t go and see it for yourself. Go ahead and talk with your team, the people who do the work. Respectfully ask questions to understand the situation from their point of view.

After you know the process, define the problem. What is the gap between the expectation or goals and the current results? Describe the current situation using data, charts, tables or diagrams. Use tools like the 5 Whys and Fishbone diagrams to understand why that gap exists. It is critical for success that you identify the root cause of the problem. Otherwise, you will be working with symptoms and not the real problem.

Engage the team in the discussion of possible solutions. Go to gemba again and brainstorm with the people doing the work. If you find more than one root cause, rank them according to which has the greatest impact on the problem. At this point, you should have all the information you need to propose countermeasures or possible solutions. Tie your action items with the root cause while creating the plan. Who is responsible for doing what? How? Where? By when?

During this initial step, you determine the success of the PDCA exercise. You are trying to formulate theories to explain the gap between the standard and current performance, without the complete information, your theory will be wrong.

CI 101

What is PDCA?

Have you ever tried to solve a recurrent problem over and over without success?  Do you remember everything you tried?  How much time do you spend on defining the problem?  Do you understand what the problem is?  Do you understand the process you are trying to fix?  Maybe, part of the problem is that you don’t have a method for problem-solving.

The PDCA cycle is a problem-solving methodology applied by many organizations in different industries.  Remember when you were in school, and you learn in science about hypothesis and experimentation?  PDCA is a way to test different theories in a controlled environment.  It is based on the scientific method, a process used by scientists to test whether any statement or theory is accurate.

PDCA stands for Plan, Do, Check, Act.  There are a couple of variations or names for it, like PDSA (Plan-Do-Study-Act), Deming Wheel, and Shewhart Cycle.  The cycle is a four steps model for problem solving and processes or services continuous improvement.  Below is a basic description of each step.

After you recognize an opportunity for improvement or a problem, you start with the first step, Plan.  As the name indicates, during this step you plan the activities and set the goals for your experiment.  It is important to understand the situation and analyze the problem, or opportunity before developing theories about what the issues may be.  As soon as all this is clear, decide which one to test. 

During the second step, Do, you test the solution.  You carry out a small-scale study by completing the planned activities, including measuring the results.

In Check, the third step, you study or analyze the results, and decide if the hypothesis is correct or not.  What did you learn?  Did you accomplish the objectives or goals stated during the Plan step?  

The last step is Act, where you take action based on the previous step learnings.  If the objectives were not accomplished, you need to go through the cycle again.  If the test was successful, use what you learned to improve the process.  While implementing the solution, do not forget to change the standard work and communicate the changes to the team.

PDCA provides a standard method for problem-solving.  While you document each step, you keep a map or journal of everything you tested so far.  You know without guessing what works or not.   PDCA is simple to follow and is an excellent tool for any kind of improvement activity like, designing a new product or implementing changes in a process.  With PDCA, you will not find yourself scratching your head trying to remember what you tried before.