5 Whys (+6-Page Lean PDF +Video +MP3 +Form)

The 5 Whys problem solving tool helps you with root cause analysis. It gets you to the heart of a problem. When you identify an issue or an abnormal condition, ask why it occurred. But don’t stop there. Continue to ask 5 ‘Why’s?’, or at least continue until you can no longer identify another cause. That is the point where you have found the core of the problem—the original reason it happened.

The 5 Whys Form

Click this image to download a free 5 Whys Worksheet

There might not be exactly 5 “Why’s?”—five is an arbitrary number to remind you to dig deeper into the problem and get past the surface explanation. A run through the 5 whys analysis, though, is usually enough to get to the heart of the issue.

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Put yourself into the 10 year-old mindset. Anyone with children has experienced the repetitive ‘Why?’ questions that children ask as they try to make sense the world around them. Kids are eager to learn.

Somewhere along the way, though, adults lose that craving for understanding and settle for the easy answer on the surface. So, what happens if you don’t dig deep enough into an issue? Well, you waste a lot of time and energy because you end up addressing a symptom instead of the real problem.

The 5 Whys prevent you from spending limited resources fixing symptoms instead of resolving problems.

If you don’t eliminate the root cause of a problem, the same symptoms will probably return in the future. Take a moment to look at the following examples.

The 5 Whys Example in Lean Manufacturing

The 5 Whys Example in Lean Manufacturing

The 5 Whys Example in Lean Manufacturing

The 5 Whys Example in the Lean Office

The 5 Whys Example in the Lean Office

The 5 Whys Example in the Lean Office

Think about what you might do if you were to ask just one ‘Why?’ and then stop. You might just replace a seal on the machine, or put additional people on the phones. In both cases, the action would be much less effective than spending a little more time trying to get to the root cause.

One other point—the 5 Whys can be done as a group exercise. In fact, when groups work together, they often challenge assumptions more than individuals do, leading to a better outcome.

As simple as the 5 Whys sounds, you will have to watch out for a few pitfalls. First, don’t be overly aggressive at trying to get exactly five ‘Whys?’ You might get to the third one and will just run into a wall trying to find a fourth. You could already be at the root cause. Five is a guideline rather than a hard and fast rule.

You might find some bias in the answers you get. Most individuals have a natural inclination to look away from themselves or their team for the source of a problem. It might take some effort to focus the search inward to get to the real root cause.

Bias also shows up when a team thinks they already know the root cause. The group often, intentionally or unintentionally, directs the flow of the 5 Whys to get to a predetermined answer. Look for lapses in logic where the next ‘Why?’ doesn’t quite follow the previous one. People from different work groups might answer the same question in very different ways.

From Our Root Cause Analysis and 5 Whys Training Module

There is one big drawback to the 5 Whys. It is not scientific in the slightest. It draws exclusively from the opinions and observations of the people doing the task. In fact, several people in the same workgroup may come to different root causes, or the same person might come to a different conclusion if they did the 5 Whys again a short time later. Because this tool is not repeatable, don’t use it by itself in critical situations. Use the 5 Whys to get the analysis going, but confirm the results with more robust methods.

In non-critical situations, though, where speed is important, the 5 Whys is an extremely useful tool. It forces people to look deeper into problems than they would if they just winged it. The extra effort of looking more critically at a problem generally brings about better outcomes. One way to improve results is to try different paths. If a ‘Why?’ has more than one possibility, see where both answers take you, and then look into both root causes that you come up with to see which is more likely.

Finally, figure out who the right people are to answer your ‘Why’ questions. Sometimes, answers are elusive. The person who knows the next ‘Why?’ might be the night shift maintenance tech, or the sales rep for the Great Plains states. The 5 Whys relies heavily on experience to know where to look. Don’t leap to a guess about why something is happening. Take the time to find someone who knows.

How does using the 5 Whys benefit you? Quite simply, it removes frustration. Most employees can give countless examples of problems that just won’t go away—despite repeated attempts to address them. Many of these difficulties can be traced back to improvement efforts that target symptoms, rather than the root cause. When that happens, the issue goes away for a little while, but comes back, seemingly stronger than ever, and reduces job satisfaction in the process. Go after the root cause to prevent that frustration.

The purpose of the 5 Whys is to conserve resources, which will likely make your life easier and help you hit your targets. The real benefit? You can quickly train your team to put the tool to use. Because of its simplicity, as well as the ‘Aha!’ moment that comes with finding the real root cause, it is one of the easiest tools to get your team using on their own. And they will not only use it, they will taste success at making things better. This tool is great at planting the seed of continuous improvement.

  • Use the 5 Whys to get to the root cause.
  • Correcting a symptom, instead of the real problem, wastes resources.
  • Correcting a root cause gets rid of problems permanently, improving satisfaction.
  • Watch out for bias.
  • Spend time finding the right person to answer your questions.
  • Be careful not to rely only on the 5 Whys for critical problems.

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