Glossary

Five Whys

The “five whys” is a lean manufacturing problem-solving technique aimed at finding the root cause of a particular problem instead of the surface-level causes. This technique was developed by Sakichi Toyoda, the Japanese industrialist, inventor, and founder of Toyota Industries in the 1930s. On the surface, it looks like a basic technique, but it can help companies find the causes of some of their most complex problems. 

Several companies around the world have used this technique to solve complex problems in manufacturing and many other operations. In Toyota, decisions are made using the “go and see” philosophy derived from the five whys methodology. With this philosophy, decisions are made after analyzing what is on the ground and not by making assumptions in boardrooms.

How does the five whys methodology work? 

When you encounter a problem, you have to ask yourselves, “why?” at least five times before making conclusions. This enables teams and individuals to find the root cause of the problem and not just the symptoms. The fifth answer to the “why?” question is usually the root cause of the issue at hand.

Asking five whys allows teams to think outside the box and look for real solutions beyond the obvious answers that everyone would suggest when assessing a particular problem. For example, if a machine in the factory breaks down, here is how you can use the 5 Whys methodology to determine the root cause. 

Your start by asking yourself why the machine broke down. The first answer would probably be “because the failure was not detected in time.” So, you ask yourself why the failure was not detected in time. The answer could be that “the person in charge wasn’t notified in time.” You should ask the third why. The answer to the third why would probably be “the maintenance system doesn’t have a mobile app with real-time notifications. “

Ask why the mobile app doesn’t exist. The answer could be that “the app developer of the maintenance system didn’t create one.” You should ask again why they didn’t create the mobile version of the platform. The answer could be that “the developer doesn’t have the expertise to develop mobile apps.”

From the above example, you notice that the root cause of the machine failing is that the developer hired to build the company’s maintenance system is not competent enough to create all the necessary tools your team needs to detect problems in time. At this level, the responsible parties know the real problem that needs to be solved. 

Effectively implementing the five Whys methodology.

If not well implemented, your team may go off track when finding answers for the five whys. Before using this method, it is best to put together a team with the skills and knowledge to understand the problem at hand. This makes it much easier to find the most accurate answers for all the five whys. 

It is also essential to clearly define the problem so that everyone involved in determining the cause understands it well enough. When the problem is clear to everyone, finding the answers to all the Whys becomes easier. 

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