Have you ever gotten into a discussion of why? because. Why? because. Last weekend I had the great pleasure of this discussion for what seemed to be the first time. I never really put much thought into it but asking why never really was a difficulty for me.
Oftentimes when we want to use the 5 whys to drill from issue to root cause we end up in a pattern of why, because. Why, because. Or, we conduct a long analysis only to find out that none of our levels of causation matched at all. One of the best known examples of a 5 why analysis was performed by the master Taiichi Ohno. He used the example of a welding robot stopping in the middle of its operation. Like a sensei does he naturally went from initial issue to root cause with almost no difficulty at all. So, how do we begin developing this level of mastery with regards to root cause analysis? Here are a few important things to keep in mind when looking for the ROOT cause.
R - reveal the general information associated with the issue. Going to the gemba and seeing the actual issue recreated will help align your thoughts with the current state of the process. If necessary you may want to create a VSM, cause map or tree diagram to make the issues more obvious. Be sure to capture basic elements such as; was the item manufactured or purchased, what was the part or service number and the date of occurrence. Finally be sure that a clear problem statement is defined. A problem statement includes who, what, when, where and how the problem was created.
O - Be sure the Operator is available when you conduct your root cause analysis. He or she will be one of the most valuable pieces of the puzzle. This often can mean involving a team or a department.
O - Begin with the obvious. Once you have seen the process through whether at the gemba or mapping and you have a clearly defined problem statement we are now ready to start "digging." You can begin with a general description of the problem then ask, why did the problem occur? Continue drilling down through the five why's until a proposed root cause is reached.
T - Test the "root cause." Though it may not seem like it, most solutions fail not because the solution itself was wrong but because the root cause was not actually a root cause. Chances are if you reach a root cause associated directly with a person it has more to do with the process the person was performing. The root cause should also be traceable back up to the visible issue. You can do this by taking your root cause and adding therefore back up to your initial description. If the story makes sense you have gotten to the root cause. If the story does not make sense simply start your analysis over. You may need to re context your questions or provide stronger correlation at some level of the 5 why's.
Root cause analysis is a critical piece of the solution puzzle. Whether you are a beginner or an advanced facilitator of root cause having a standard pattern, method or kata to develop your skills through application is very helpful. If you are interested in obtaining a 5 why template, click on the button below. The template is formatted in such a way that through repetition of the tool you will train your mind to naturally shift from the issue to a problem solving process, just as Taiichi did. How did you first learn about the 5 why analysis?