Why Do We Fear Defects, Mistakes and Errors?

Six Sigma can reduce or eliminate defects, mistakes and errors, but it presupposes that data about these glitches is readily available. I have found that almost every department in every company keeps track of defects, but rarely does anything about them. I have also found that the person holding the data doesn't really want to hand it over for analysis because they are supposed to be in charge of fixing the problem.


In Kathryn Schulz's book, Being Wrong, she investigates our love of being right and fear of being wrong—what she calls Wrongology. In a business culture that blames people, not processes, employees tend to hide or minimize defects. It's very difficult to get the data needed for Six Sigma in a people-blaming culture. In a culture that blames processes and systems, every defect can be seen as a learning event. Data is much more readily available in this kind of culture.

We don't assess evidence neutrally; we assess it in light of whatever theories we've already formed on the basis of whatever other, earlier evidence we have encountered.

In almost every improvement project, I have found that team members come in with their own pet theory about the root cause of the problem. Using confirmation bias, they usually try to find data to support their hypothesis and creatively dodge opposing evidence. After I analyze the data, I invariably have to help them see where the problem lies and then guide them in root cause analysis to find the real root cause.

For example, when I worked at the phone company, telephone repair managers wanted to prove that they needed more people. I tried, unsuccessfully, to convince leadership that we needed to find ways to reduce the need for repair (defects). After testing their countermeasure for two months, the project failed.

In healthcare, nursing managers think they need more nurses to achieve better patient outcomes, but when we redesign the nursing unit using Lean and put supplies where they are needed, the unit no longer needs more nurses. Patient outcomes improve and nursing satisfaction soars. As the Lean sensei's often say about solutions: no money, no time, no people. Some of the most effective countermeasures to eliminate errors require no money, no time and no people.

What Stops Us From Embracing Errors and Their Countermeasures?

  • Our cultures tend to support our own ideas
  • They shield us from outside disagreement
  • They make us ignore whatever outside disagreement we receive
  • They squash disagreement from within
  • We are overconfident and risk-averse

What Is Good About Mistakes?

Most of us find it difficult, if not impossible, to say, 'I was wrong; I made a terrible mistake.'

-Elliot Aronson and Carol Tavris

In Alina Tugen's book, Better by Mistake, she suggests that the aftermath of mistakes—tracing back why we made them and what we learned from them can be very helpful in avoiding mistakes in the future. In other words, mistakes are good because they provide a learning event. Unfortunately, most harried employees simply develop workarounds to mitigate mistakes instead of changing the system to prevent them.

What Do We Need to Do Differently?

We learn from mistakes, but the reality is that most of us hate and dread them.

- Alina Tugen

  1. Accept the likelihood of error. The unexamined process becomes more error-prone over time.
  2. Be open to discuss defects, mistakes or errors; distrust inhibits openness.
  3. Systematically collect information about mistakes. Without measurements, defects cannot be counted, categorized and corrected. Without measurements no one knows what causes errors or how to resolve them.

These are just a few of the thoughts contained in these two books. To be able to solve the problems facing most businesses, we need to understand the psychology of defects, mistakes and errors. Like most Six Sigma projects, people's thoughts, fears, and hallucinations about the problem and its cause can be the hardest barrier to success.

Rights to reprint this article in company periodicals is freely given with the inclusion of the following tag line: "© 2016 Jay Arthur, the KnowWare® Man, (888) 468-1537, support@qimacros.com."

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