The Five Whys

There is one enduring principle of business: problems will occur, things will break, and sh*t happens. When problems do appear, the temptation is to blame others or external events. But the root cause often lies closer to home. When trying to solve a problem, it helps to begin with the end in mind (the presenting problem) and work backwards toward the root cause. Invariably one finds that the cause is not a person or external event, but a system failure.

A problem-solving technique called the Five Whys uses a questions-asking method to explore the cause-and-effect relationships underlying a particular problem or defect. It asks the question “Why?” five times to get at the root cause of a problem. Many children use a variation of this technique when they continue to ask “Why?” after each answer given by their parent (but no doubt for different intended results). The Five Whys technique was developed by Sakichi Toyoda for the Toyota Motor Company as a systemic problem-solving tool. There are a few simple steps to applying the Five Whys technique:

1. Gather a team of people together who are acquainted with the problem, and as a group develop the problem statement. It is important to involve anyone who might be familiar with the problem or affected by it. If an important person is absent from the process, the team may resort to what Eric Ries, author of The Lean Startup, calls “the five blames” or scapegoating.

2. Ask the first “why” of the team: “Why is this problem taking place?” There may be more than one sensible answer to the question, so record several of them on a flip chart or whiteboard. The answers to the question need to be honest, as systemic as possible (instead of just resorting to blaming people), and agreed upon by all members present.

3. Take each possible answer in turn and continue to ask “Why?” four more times, posting each answer in succession like branches of a tree.

4. If necessary, continue asking “Why?” beyond the arbitrary five number until you get to the root cause. You may even discover the root cause in less than five whys. Ries reminds us that the best root cause is generally systemic and intuitive in nature: “Most mistakes are caused by flawed systems, not bad people.”

5. After agreeing on the most probable root cause of the problem, develop appropriate corrective actions to remove the root cause from the system.

Here is an example of the Five Whys technique applied by Jeff Bezos of

The Problem: An employee in the fulfillment center damaged his thumb.

1. Why did the employee damage his thumb?

Because his thumb got caught in the conveyor.

2. Why did his thumb get caught in the conveyor?

Because he was chasing his bag which was on the moving conveyor belt.

3. Why was he chasing his bag?

Because he had placed his bag on the conveyor which had suddenly started moving.

4. Why was his bag on the conveyor belt?

Because he didn’t have anywhere to place his bag and was using the conveyor as a table.

Therefore, the root cause of the employee’s damaged thumb was that he simply needed a table. There were no tables or lockers provided for employees. The solution was to provide adequate storage spaces for employees and to update safety training.

The Five Whys technique is not the end-all of problem-solving techniques, but it is simple, straightforward, and can be easily learned and applied by most employees. It may not be appropriate for higher-level problems, and only will work if the participants put in the effort to develop answers beyond mere symptoms and blaming. The process may also yield better results if the discussion is moderated by an employee with some authority and who has experience leading Five Whys discussions. Start with your lower level problems to gain familiarity with the technique, and avoid the temptation to try and solve your most vexing problems first.

So, what problem are you facing that could benefit from the problem-solving benefits of the Five Whys?

Kent Wilson (PhD) is a business practitioner and leadership specialist. After running companies for 30 years, he now serves as an executive coach with Vistage International and the Nonprofit Leadership Exchange in Colorado Springs. He can be reached at