5 Why’s

What is Five Why’s

Problem Root CauseCorrective

Action

5 Whys Tool

Five why’s is one of the many Root Cause Analysis Tools.

The outcome of a 5 Why’s analysis is one or several root causes that identify the reason why a problem was originated.

Five Why’s Preparation

It is not always necessary to reach 5 before the root cause of a problem is fully explained

It may take more than 5 why’s to get to the bottom of the problem which could depend on the complexity.

5 is the accepted rule of thumb, by which most root causes are clearly identified.

For all the Five Why’s:

Ask the full question including the problem or cause behind it.

If the answer is XYZ, then ask: why it was XYZ?

If we do not follow this approach answers to the why’s tend to lose focus on the third or fourth why.

Five Why’s Preparation

It is absolutely true that a well defined problem is a half resolved

problem. Hence state the problem as clearly as possible. Define the problem in terms of the requirements that are not

being met. So we have a reference to the condition that what it should be

and is not.

Five Why’s – The First Why

State clearly the reason for the failure to occur.

The 1st Why should be a concise statement that explains the reason in clear terms.

Document it even if it very simple and so very patently clear.

Justification for the “reason” needs to come only later that too only if it contributes to the entire 5 Whys process.

Five Why’s – The Second Why

A more concise explanation to support the first statement.

Get deeper into the technical arena, the explanation can produce several different root causes.

Follow each of them with their own set of remaining 3 why’s.

Five Why’s – The Third Why

Most important note at this time: Do not jump into conclusions or rush into “logical explanations”

Continue the regular thought process even if you can figure out some underlying root causes slowly surfacing.

This 3rd why is very critical for a successful transition between the “obvious” and the “not so obvious”.

The first two why’s have focused on the area where the problem could have originated

The last three why’s will take you to a deeper comprehension of the problem.

Visualize the process (process mapping) and narrow down to the most likely sources for the problem to occur.

Five Why’s – The Fourth Why

Set side any preconceived explanations Start the fourth why with a candid approach You may have several different avenues to explore now, explore them all. Even if one or several of them turn out not to be the root cause of the problem, they may lead to continuous improvements.

This is a good time to include a Cause and Effect analysis and look at the 5 M’s.Method

Materials Manning

Machines Mother Nature

Five Why’s – The Fifth Why

When you finally get to the fifth why…….

A systemic cause would have been found Most of the failures in the process can be traced to this cause It could be lack of awareness of Preventive Maintenance Or could be lack of knowledge of correct parameters setup for

the equipment All these could finally be traced back to lack of training

Five Why’s – The Fifth Why

While addressing a systemic cause, do it across the entire process and detect areas that may be under the same situation even if there are no reported issues yet.

And last but not the least……….

If you have reached the fifth why and you are still dealing with process related cause(s), you may still need one or two more why’s to deep dive into the systemic cause.

Five Why’s – Conclusion

If the 5 Why’s has been carried out in good detail, then we should be able to organize the conclusion in one sentence and in an understandable manner.

If this cannot be done chances are that there is gap between one or several of the why’s. We need to then revisit the 5 Why and identify those gaps to fill them in.

If there is coherence in the way that the one sentence is assembled, it shows consistency on the thought process.

The one sentence conclusion would need to look something like (just an example):“Problem” occurred due to “Fifth Why”. This was caused by “Fourth why” mainly because “Third Why” was allowed by “Second why”, and this led to “First Why”.

Five Why’s – Please remember

The outcome of a 5 Why exercise is a root cause of a the defined problem, not the resolution of the problem itself This method is not a standalone Problem Solving technique but more of a tool to aid in this process.