One of the techniques that is used in the Lean Manufacturing World is “The Five Why’s”. The Five Why’s is a method of getting to true root cause of an issue or problem.

It is the practice of asking why repeatedly whenever a problem or issue arises. Below is an example (adapted from the Lean Lexicon – Lean Enterprise Institute, www.lean.org ) of what this means.

For instance, Taiichi Ohno gives this example about a machine that stopped working (Ohno 1988, p. 17):
1. Why did the machine stop?
There was an overload and the fuse blew.

2. Why was there an overload?
The bearing was not sufficiently lubricated.

3. Why was it not lubricated?
The lubrication pump was not pumping sufficiently.

4. Why was it not pumping sufficiently?
The shaft of the pump was worn and rattling.

5. Why was the shaft worn out?
There was no strainer attached and metal scraps got in.

They go on to discuss why there was no strainer and it turned out that the Preventative Maintenance Program schedule wasn’t being followed and this was the root cause of the problem, not that the machine broke down. The machine breakdown was a symptom and not the disease.

While here they were discussing a manufacturing problem, this technique can be used in any kind of problem solving, analysis or brainstorming – from analyzing financial results to problem solving sales or marketing issues.

Try it out and you’ll find that you will get to the root cause much faster and eliminate the real issue and not simply place a band-aid on a symptom.

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