When giant companies known for the quality of their products and services find themselves suddenly in the news due to massive recalls—think Volkswagen, Toyota, John Deere, Craftsman, or Chipotle—the first question to emerge often is: What went wrong?

Before jumping to the conclusion that quality systems really don’t work (so why bother?), let’s consider some of the reasons why established improvement efforts fail:

1. When a pattern is established within an organization of producing only good products, a sloppy approach to assuring quality may result. Quality efforts are sustained, but often only under pressure from problems. These may include excessive waste and cost, which demand some kind of action to reduce defects. When things are going well, this pressure may be felt less keenly.

2. Failure to understand variation in processes can lead to out-of-control situations. If spec limits have been substituted for control limits, for example, process stability can’t be ensured.

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