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The “5 Whys”: What Are They?

The 5 Whys are a very simple method of getting to the root cause of a problem or an opportunity.

They are often used after narrowing down our problem by starting with a Fishbone diagram, which separates the problem into different areas like People, Information, Process and Systems.

The Five Whys method is based on continuously asking “Why” something occurs until the real problem is revealed.  For example, a job in your company might be taking longer to complete than it should to complete.

“Why?”  The job is held up in one department with large backlogs of work.

“Why?”  They have to wait for information from multiple sources.

“Why?”  No one knows what information is specifically required to complete the process.

“Why?”  The correct information has not been made visible or easily accessible.

We can validate our “Five Whys” by reversing them and replacing “Why”, with “Therefore”.  If it still makes sense, then there is a good chance we have a valid root cause.  Here is an example:

The correct information has not been made visible or easily accessible.

“Therefore”, no one knows what information is specifically required to complete the process.

“Therefore”,  they have to wait for information from multiple sources.

“Therefore”, the job is held up in one department with large backlogs of work.

“Therefore”, a job in your company might be taking longer to complete than it should to complete.

When we have our possible root cause to the problem, we can delve deeper by gathering any required data, timings, rework and making is visible with a Value Stream Map, and then see where to start using the 80/20 rule and a Pareto Chart.

When implementing the 5 Whys, we don’t necessarily have to ask Why five times, five was simply noted to be the most common amount of times asked before the true root cause was revealed.

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