The 5 Whys

By Penny Macias | November 17, 2016

There are several tools we use in LEAN/Six Sigma to help improve a problem. One of my favorites is the 5 Whys. In LEAN/Six Sigma, we use the DMAIC approach to improvement. DMAIC is short for: Define, Measure, Analyze, Improve, and Control. When we "analyze," we are trying to find the root cause(s) of a problem. The Root Cause is the thing or issue, that if fixed, should eliminate the problem all together. Sometimes, what we think is the cause, is actually a symptom. We have to dig deeper to see the real root.

Before we do the 5 Whys' exercise, we can look at all the things we think contribute to our problem and then test our ideas to see if those are real root causes or symptoms. For example:

Problem: We Need More Staff to Process Applications

  1. Why? We receive 100 applications a day and can only complete 15 a day.
  2. Why can we only complete 15 a day when we have a staff of five people? Adam has to finalize each one, which takes him 30 minutes per application during an eight-hour day.
  3. Why does Adam have to approve every application? He is the only one who has the software on his computer to print the final paperwork
  4. Why is Adam the only one with the license? We never paid the $150/person for extra licenses.
  5. Why didn't we pay for additional licenses? We didn't think anyone else needed them when we signed up and we haven't revisited it since.

So the root cause here is: We don't have enough software licenses because we haven't made it a priority to pay for and get additional licenses. I hope you realize the answer depends on the specific situation and there's likely more than one root cause.

One thing to note in the example's initial assumption was, "We need more people." However, by going through the 5 Whys' analysis, we determined we didn't have enough of the right equipment. If we had stopped before we got to this answer, we might have designed the wrong solution to our problem. Imagine how frustrating it would be if we added another person to the process and still were only completing 15 applications per day.

Finally, it's called the 5 Whys but five is not a magic number. There will be instances where you have to ask "why" three times or even 10 times. It all depends on your problem.

I hope this illustrates how useful this tool is and will inspire some critical analysis when you hear what someone assumes is the answer to a problem. If you have any problems utilizing this method and need help with analysis, please reach out to the MAAP. You can contact me or Robyn, or any of the MAAP Champions you know. We are all happy to help others try out our tools.