This seems to be over-simplified, from the medical device manufacturing perspective. If you accept making more defects, you at least need to understand the strain this will put on your detection system and have bullet-proof measurement systems analysis for it. You can not assume all defects are routinely caught; the more of them your process produces, the greater the risk may be for them not to be contained. If that defect can cause a serious device failure, you may not be able to accept lower sigma performance based strictly on a cost analysis.

This article would be good if it only considered manufacturing quality, and the consumer risk was low and the perfection of inspection was high. There is a big difference between, "This light bulb doesn't light up," and, "Our aircraft is falling out of the sky." This type of economic thinking gave us the trucks with the exploding gas tanks because it would cost more to have an improved design than the projected cost of the legal costs from the families. Too many people in management downplay the real cost of failures. If you improve products to a new level, you can gain more business. True, you can try to substitute inspection for competance, but how good does your inspection have to be to compensate for your process limitations?

Good perspectives from Nebula and JAE - the organization needs to ask the right questions based on its value and missions. I generally believe in chasing perfection, but perfection needs to be carefully identified, along with attendant costs and resources, up front. Yes, I know I'm preaching to the choir.