The five whys?

We are often presented with a simple problem, that requires a simple solution. But what if the solution we implement only places a plaster over the issue and doesn’t prevent it from happening again in the future?

Taiichi Ohno, the father of the infamous Toyota Production System (TPS), was known for experimenting with different management techniques to increase productivity.

Ohno discovered after a trip to Ford’s flagship manufacturing plant in Detroit, that workers who were assembling cars were aware of minor issues with parts, but powerless to react. Instead they would continue keeping pace with the line, rather than re-work the vehicle. The car would be placed in a designated re-work area at the end of the production line, where another team would rectify the defects. Bearing in mind that the cars were made up of thousands of parts, re-work was not always a simple exercise.

At the time, Toyota was not producing anywhere near as many cars as Ford, so didn’t feel the urge to maintain a fast pace on the production line. Consequently, Ohno decided that problems should be solved as they are discovered and furthermore the root cause must be identified in order to prevent it from happening again.

Ohno formed a problem-solving technique called “the five whys”. He started by empowering each of his workers to stop the production line if they identified a problem, a level of autonomy unheard of at Ford. The team would then lay down their tools and inspect the problem together using “the five whys”.

The first step in the process is to clearly identify the problem you are trying to solve. It might sound obvious, but being specific is important. Then, as a team, start the interrogation; here is an example from the manufacturing sector:

The problem: At Ford motor plant post-production, the car won’t start

Why 1? Oil is leaking from the engine.
Why 2? The oil tank does not fit this model vehicle correctly.
Why 3? The supplier has provided us with the incorrect part.
Why 4? The part has been mislabelled and is for a different vehicle.
Why 5? The supplier did not quality control the order before it was sent to us. (This is the root cause)

Solution: Instruct the supplier to put in place better quality control procedures and penalise them for any errors.

When this is first implemented, you may find that your team stops regularly as they identify problems. This should not be discouraged as the long-term impact is what makes this so effective. As the problem-solving capacity of your team develops, problems will be identified and resolved faster, to a point where work hardly stops at all.

You should find that the team develop stronger relationships through closer working and morale increases. In addition, the quality of your final product will improve.

Root cause analysis is an important part of the evolution of your business. If you are going to be able to compete in any industry, you must solve your problems faster than your competitors. If you fail to tackle the root causes of problems, you risk dying a death of a thousand cuts and losing valuable ground to the competition.


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