5 Why 101 – Everything You Need to Know

5 Why 101 – Everything You Need to Know

The 5 Whys problem-solving method makes use of a very easy iterative approach in attempting and analyzing to find the root cause of a problem. In case you didn’t know yet, the 5 why technique comes from the Toyota Manufacturing system founded in the country of Japan by the Toyota car corporation. The idea consists of defining the problem in a problem statement and asking why is this the case, or why is the concern what it is. This method often times approaches in a team setting and can involve brainstorming as a concept generation process to determine potential causes.

How does it work?

If you want to bring about huge change in the way your company functions, you must start utilizing the 5 Why in order to deal with any issue. It’s extremely easy to use and it involves the asking of a question after the other to get the root of any issue. The first why make an answer that must quick another why and so on. Some of the perks of utilizing this method for problem-solving are the following:

  • There’s a rarely any need to gather data for utilizing this tool and doesn’t call for statistical analysis of any kind.
  • The process unearths a whole of many problems, which are connected to the main problem.
  • It aids you to get the genesis of an issue so that it can be managed right at that point. Trying to deal with the symptoms of an issue doesn’t amount to anything but window dressing.

In the following examples a production problem, the 5 why a problem-solving method is appropriate to use because of the problem requires to be found quickly and tends to not need a complicated fault finding the procedure.


A production process found in the food manufacturing sector that generates potato chips in a continues production line, at the same time has a production problem where during testing of food productions samples, the potato salt levels are very high continuously in all samples taken over the last time. A solution for this problem should be found promptly as because to being food manufacturing each production out of spec isn’t able to be purchased.

  • 1st Why: Too much salt feeding throughout the process
  • 2nd Why: Probably fault along with the salt feeder equipment
  • 3rd Why: Failure of measurement paddle cell

In the given example, we’ve reached a probable root cause for the production issue by asking Why several times, this will depend on the issue being analyzed. Below are the corrective and investigation actions that should be carried out to approve the root case as true. If the probable cause is found to be not correct, the Why could be repeated until the real root cause is determined.

In other cases, an answer or cause to one of the Why’s could itself be caused by some failures or issues. In the given example mentioned, the disaster of feeding equipment could be triggered by improper weight readings coming from the salt feed bin down to the process controller or maybe a failure of the process controller too.

— Slimane Zouggari