The Five Whys Exercise

The Five Whys Exercise

Designing, engineering and manufacturing cars is one of the most complex industrial processes on earth.

The number of things that can go wrong is innumerable.

This makes the consistent reliability of Toyota cars all the more remarkable - as they very rarely break down.

Don’t believe me? Just ask someone who owns one.

What is it that lies behind their success?

A very deliberate attempt to diagnose any problem properly.

They’ve learnt the importance of asking the right type of questions to better understand the relationship between cause and effect.

The five whys exercise is an iterative interrogative process that aims to get to the root cause of a problem.

Since we’re discussing Toyota (who famously use this exercise) let’s look at a car related problem by way of an example.

The vehicle will not start. (The problem)

  1. Why? - The battery is dead. (First why)
  2. Why? - The alternator is not functioning. (Second why)

  3. Why? - The alternator belt has broken. (Third why)

  4. Why? - The alternator belt was well beyond its useful service life and not replaced. (Fourth why)

  5. Why? - The vehicle was not maintained according to the recommended service schedule. (Fifth why, a root cause)

As you can see from the exercise above it is only on asking the fifth question the root cause is correctly established.

The Similarity Bias

The Similarity Bias

Why Your Brilliant Idea Is Worthless

Why Your Brilliant Idea Is Worthless