#NowIUnderstand glossary:
the 5 Whys method of problem resolution

Jun 14th, 2018
The 5 Whys glossary: definition and applications

The 5 Whys method is an extremely effective way to quickly detect and determine the underlying causes of malfunctions. It is the Swiss Army knife of problem-resolution techniques, to be wielded in any situation. Our user guide will explain why it is used, and how to use it effectively.

What is the 5 Whys method?

The technique was originally devised by the founder of Toyota Industries, Sakichi Toyoda. Subsequently, Taiichi Ohno, the Japanese industrial engineer considered to be the architect of Toyota’s production system, described how this iterative questioning method could serve to identify the fundamental cause of any observed phenomenon, such as a decline in sales, or a safety risk, a product quality failure, and so on.

The technique is nothing more and nothing less than asking “Why?” five times, each time delving a little deeper into the causes of the problem. Empirically, such repetition makes it possible to reach the root cause. However, asking “Why?” five times specifically is not mandatory, and the figure can vary from situation to situation, with more or fewer iterations depending on the complexity and/or nature of the problem.

The 5 Whys method can also be used in a continuous improvement context or in project portfolio management, or even to support the development of innovation, as it helps find solutions to all types of problem raised.

What is the 5 Whys method used for?

Starting from an observed effect, the aim is to go back to the “true” cause of the problem. Rather like the way Chinese medicine views the body rather than treating symptoms, the 5 Whys method looks for the real sources, in order to eradicate problems, definitely and permanently. In this sense, it is a genuine tool for continuous improvement making it possible to identify strategic improvement areas to guide the right decisions.

The method naturally has its limitations, such as where issues are complex and multifaceted, but it can be helpful in resolving vast numbers of problems at all levels of the business.

How is the 5 Whys method used?

The method is a simple one: when a defect or failing is detected, ask yourself why. But it goes further, by then refining the question and asking “Why?” again, five times. It can also be beneficial to combine this technique with the 5W1H method to cover all possible causes, such as the persons concerned or in charge, the place, the object of the malfunction, and so on.

The method excels when it is used participatively, working with those directly affected, and travelling to the location of the problem to see the fuller picture. But rather than a long-winded explanation, practical examples of applying the 5 Whys method will be more meaningful…

A commercial example of the 5 Whys technique

Let us take the case of a company in B2B with sales facing a substantial drop in the volumes sold to its regular clients:

Why has such a drop occurred?

Loyal clients were in the habit of renewing their orders when the sales person called. Sales representatives now visit them less often.

Why are sales representatives visiting regular clients less often?

The sales targets set for this year are encouraging sales representatives to sell a new range of products, which are intended for a new market.

Why was this objective set?

There was a need to motivate sales staff to seek out more leads.

Why were sales staff not doing enough sales lead generation?

They used to have sales targets linked to current product ranges, easier to sell to regular clients.

Why were they unable to both retain clients and find new ones?

Because there were not enough sales representatives in the field compared to the number of clients and leads to be visited.

The sequence of “Whys” enables the situation to be analysed while also finding avenues leading to solutions to the “real” problem, those solutions being to recruit more sales staff, review the geographical split into sales territories, change sales targets, etc.

An industrial example of the 5 Whys technique

This time, let’s look at a case of a workplace accident in a workshop. An operator has slipped and broken his elbow:

Why did he slip?

There was a patch of oil on the floor.

Why was there a patch of oil on the floor?

The machine has been leaking for a week.

Why has the machine been leaking?

Because of a maintenance failing. The machine should have been repaired.

Why was the machine not repaired immediately?

Because the maintenance technician is on holiday.

Why is there no replacement maintenance technician?

He is the only person trained to repair this type of machine.

What is the problem? The machine needs to be repaired to prevent another accident occurring, but to do that, correct monitoring of maintenance must be organised. This includes ensuring the availability of a) spare parts in advance and, of course, b) an individual able to carry out the work. The aim in future is to put a preventive measure in place, by training other people in maintaining this type of machine.

If you want to eliminate the underlying cases of malfunctions and quality failings in your business, download our e-book to find out about best practice in action plan management: