Moving the Goalposts

In Out of the Crisis, Deming lists some of the comments that he heard while working with various companies, and which he saw as symptomatic of the malaise of American industry. First on the list was the following:

The customer's specifications are often far tighter than he needs. It would be interesting to ask a customer how he measures the items that he says must conform to his specifications, and why he needs the tolerances that he specifies.¹

Such sentiments are dangerous, because they assume that there is room for argument about what constitutes a 'good' part. There is not. Specifications are 'the voice of the customer' and must be respected as such. Your customer knows better than anyone else what is acceptable, and what is not.

If one focuses on the product and not the process, there is only one way to reduce the fraction defective. That is to 'reinterpret' the specifications so that a greater percentage of the output can be passed first time. This will be a particular problem if people feel under pressure from quotas and shipping deadlines that have not been established scientifically.

The simple fact of the matter is, you cannot move the goalposts just because you keep shooting wide. In order to achieve consistent output that meets the specifications, and to strive for the best possible quality, there is another voice you need to listen to....The Voice of the Process.