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The "5 Whys"​ Method (5Ys) - how to collaboratively identify and solve the root cause of problems

The problem you are facing might not be the real problem you are facing.

There might be another problem making the current problem occur. A cause to the problematic effect which is the real problem.

Without addressing the cause the problem will simply reoccur.

The founder of the company which is now Toyota knew this. Sakichi Toyoda (1867 – 1930) was an inventor and an influential figure in the Japanese industrial revolution. He is accredited to creating the 'Five Whys Method' - a simple but powerful tool for getting to the route of a problem. Its become known as "The Five Whys" (or simply 5Ys) and is part of the Toyota Production System.

Sakichi Toyoda - Source: Wikipedia

What is the "5 Whys" Method?

Like all of the best tools, "5 Whys" is easy and simple. When you come across a problem you ask "Why" it has occurred. After each answer, you ask "why" again. Five times. At each stage, you can consider putting "countermeasures" in place which can help to ensure that the stage of the problem does not occur - basically preventing the initial problem from happening.


Here is a crude example of how it works:

  • Initial Problem Statement: "The electricity in our factory keeps tripping causing a 30 min downtime in productivity".

  • Why 1: "Staff are spilling drinks that they are carrying over an electrical power supply".

  • Why 2: "Because they keep colliding with each other whilst travelling from the canteen to his workstation".

  • Why 3: "Because they are thirsty and want to drink at their workstations".

  • Why 4: "Because company policy is such that the time allocated for breaks does not allow staff time to finish their drinks within the time of the break".

  • Why 5: "Because HR worry that to allow longer breaks will mean we will be less productive".

You could keep going if you think there is more value in asking Why more times - or if you think you find the root problem earlier you can stop at that.

Taking the above example a team can then brainstorm "countermeasure" ideas. For example:

  • Counter to Why 1: We need to do an audit on and reposition any poorly installed electrical power sockets.

  • Counter to Why 2: We can install clear walking lanes so that people are less likely to bump into each other.

  • Counter to Why 3: We should have a policy that all drinks should be consumed in the canteen.

  • Counter to Why 4: We need to install better drinks machines which will distribute beverages quicker for our people.

  • Counter to Why 5: We need to review and make the case that having the factory go down for 30 mins is unproductive.

Obviously, this is a rough example but do you see how that at each stage the countermeasure ideas make it less and less likely the initial problem does not occur? The idea though is that if you deal with the fifth "Why" you should have dealt with the root problem and so the original issue should not resurface.

Why is "5 Whys" a good tool?

The 5 Whys Method helps teams to reason through actions which will prevent the problem from manifesting itself again. A "quick fix" solution might be helpful to address an urgent problem but not to ensure the problem does not pop up again. By using 5 Whys teams can discover "counter-measures" which address the root cause of the problem. Identifying "counter-measures" are way more robust than simply finding a singular "solution" to the surface issue.

How to Use the 5 Whys

There are so many ways you can use this flexible and dynamic tool. I've used it to help teams think about their ideal customer personas. I've used it to help teams innovate new products around customer problems. I've used it when coaching and mentoring people. I've also used it in design thinking sprints and in ideation meetings. I find its most effective though when you are using it to improve customer or employee experience.

One of the benefits of the simplicity of the tool is that it's easy to align teams around as a process - allowing for vibrant and exciting workshop sessions.

Here's a process that you can use when you come across a problem - say, for example, in your customer experience.

1. Get the right people in the room

It's important to get people together who understand the problem. Informed people with practical experience. Ideally, you would also have decision-makers in the room so that you can action outputs. Appoint a facilitator who will keep the session on track.

2. Problem Statement

This sounds easy but it often is not. As a group, you need to articulate the problem you are trying to solve clearly. Write this up on a whiteboard.

3. Ask & answer "Why?" Five times

It's key that when you answer, the answer the group comes up with is based on facts. At Toyota for example, they have a "go and see" approach which means they go and see what is really happening - they don't just assume. Unless you have facts you may go off at a hypothetical tangent.

At this point, you might have multiple options as to Why. You can still complete the exercise going down each "why" strand.

4. Brainstorm countermeasures

After you have all of the Why's in place go back through each one and then brainstorm 'Counters' to each Why. The Counter should provide a solution to the problem and prevent (or limit the chances of) it from occurring.

5. Action your countermeasures

You should be left with a set of actional countermeasures that you can then look to implement. You can then create a roadmap and assign responsibilities and milestones to make the necessary changes. I always suggest that the group also fixes a review date in the future to consider whether the countermeasures that have been put in motion did indeed solve the original issue.

Heres a handy layout you could consider using if you were running a 5 Whys session:

So - I hope that you find this method helpful. Go solve problems and change the world for the better.


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