The skill of questioning is one of the most important skills to master in the process of problem solving. I live by the principle of ‘ask and you shall receive’.
As you will now become even more aware, this principle has great significance in the process of asking questions.
Good questions generate good answers, poor questions result in poor answers. What you ask for you will get.
Asking The Wrong Question In Root Cause Analysis
So let’s put this into context.
Many students of ‘root cause analysis’ training are taught to ask questions based on ‘why’. I am totally convinced that this is not the best word to use in your questioning.
Interestingly, use of the word ‘why’ in cause and effect analysis can lead down a path that generates reasons for the outcome, not causes of the outcome.
What do I mean by that? Let me distinguish between the two in this way.
Imagine yourself driving along the road in your motor vehicle. As the vehicle travels along it suddenly swerves to the left and runs off the road, totally out of control.
This specific outcome or event can be described as unexpected variation in the path taken by the motor vehicle. To identify the cause of that outcome or event, suppose we asked this question.
‘Why did the vehicle run off the road?’
That question is potentially misleading. For example, the following answers fit this ‘why’ question.
– I wasn’t strong enough to hold the wheel straight.
– The road is only two lanes wide.
– The car swerved towards the left.
Not one of these answers takes us down the root cause path!
These are reasons why the car ran off the road, not causes that help us to solve the problem.
Building bigger muscles so that you can hold the wheel straight might help stop the vehicle running off the road, but it does not really treat the true cause of the problem.
Asking The Right Type of Question
A much more effective question to ask would be one that directs our minds toward specifically seeking out causes that help us to eliminate the problem.
‘What caused the vehicle to run off the road?’
In this case, the answers will be different than those generated for the first question. This time the answers might be:
– The steering gear failed.
– I went to sleep at the wheel.
– The front tyre deflated.
Those answers are moving closer to the actual cause of the outcome.
Questions are Determined by Context
In essence, the questions you ask during any cause and effect study should be determined by the context of your analysis.
For example, you must ask questions specifically about the cause of the event when you study a one off problem or event (a special cause). An appropriate question would be ‘what caused this event to occur?’
By contrast, you should ask about the cause of variation when you want to reduce variation in a process. In such a case an appropriate question might be ‘what causes variation in this process?’
Questions beginning with ‘why’ do have their place, but don’t simply use them out of habit. If you want good answers, ask the right questions.
More Information
This article was written by George Lee Sye, author of PROCESS MASTERY WITH LEAN SIX SIGMA – the best lean six sigma text book in the world today.