So, have there been occasions for the Zero Defects name to be applied to something totally incongruous to what Crosby and also Deming would have taught! Sure!!! Doesn’t mean they are doing it right, and it is wrong to judge what one man called Zero Defects based upon what somebody else did, using the same name.

Crosby used an analogy of the game of golf. There are rules to the game, they are specific. But on any course, you may find someone who hits a provisional ball, and so pretends to lose the worst. He may hit to a hazard, and take a drop, but not record a penalty stroke. He may five put the green, but record four and say “Mulligan”. This player is in golf clothes and shoes. He is hauling golf clubs. He is riding a golf cart. He is swinging golf clubs at golf balls and doing all of the activities of golf— but he is NOT playing golf. He is playing some game of his own personal invention, but it is not golf. Though he will probably tell anyone who listens how great the game is and how he loves golf. So if you read the rulebook, and observed this player who said he was golfing, you would conclude that Golf is a dishonest endeavor for seemingly made for cheats and liars. You might condemn the game of golf, based upon observing this “golfer” up close. The mistake—- while going though some of the motions, he was not actually playing golf, and it is completely wrong to judge golf on someone who isn’t even actually playing the game, but just using the same WORDS and MOTIONS.

So it can be with programs and processes.

As to the Six Sigma number of 3.4 defects per million, to me that’s awful close to unrealistic for the vast majority of processes as well. I have been through the training programs and I think the tools applied are of more than great utility. But plus-minus six sigma?! Is that realistic or even always necessary? I have great doubts. I find the concept of Taguchi loss function to be far more applicable in most settings.

My unsubstantiated opinion is that the original explanation to some manager at Motorola was that the engineer was promoting plus-minus 3 sigma, for a total of Six Sigma. Then it was imparted up the chain and somehow (like the game of telephone) it was confused to plus minus Six Sigma. And then, after the fact, to protect the management from embarrassment; all of the documentation became about justifying “plus-minus six sigma” 3.4 dmo. And so here we are talking about statistical thinking and realistic expectations, while at the same time promoting a with a name that is for the vast majority, unachievable.

Kind of like back in the fifties, the Lockheed Skunk-Works designed the Blackbird. One version became the RS-71 (Reconasance-Supersonic type 71). Then they decided to let the President, Eisenhower announce the plane’s existence at a press conference where he slipped and said it was the SR-71. NOBODY corrected the President or even mentioned it. From then on, everything was officially the SR-71. Kind of like (I believe) Six-Sigma total became to a high level manager Plus Minus Six Sigma. And here we are talking about 3.4 DMO like it is real or even realistic.

It will always be continuous quality improvement. There is certainly huge room for improvement for hospital falls and infections, things that have been close to my heart.

Yes, the entire Deming point is:

“Eliminate slogans, exhortations, and targets for the workforce asking for zero defects and new levels of productivity. Such exhortations only create adversarial relationships, as the bulk of the causes of low quality and low productivity belong to the system and thus lie beyond the power of the work force.”

If “zero defects” is just an empty slogan, that’s bad and counterproductive and a recipe for frustration.

But if we have a METHOD to prevent errors – for example, getting hospital acquired infections or patient falls to zero through better processes and better management (not through slogans), then that is an admirable (and increasingly achievable) goal.

Also, in your cost graph you do not account (at all) for the cost of leaving the defects in the product. That cost would be much higher when the number of defects is higher (assuming the same distribution between trivial/critical defects)

Here’s my full argument as to why aiming for Zero Defects is not only good, it’s the only way to survive long term: http://bit.ly/15lkle

In the Lean community, I personally don’t feel the proper emphasis being given to built-in quality, and I’m not sure why.

The Taguchi Loss Function demonstrates that quality cannot be inspected in, but it can be controlled through robust design. Likewise, proper equipment design can catch quality defects and stop the process before they are passed on to the customer (or the next process).

Mark is absolutely right that you can error-proof any business process, but I’m more interested in why companies don’t emphasize DFx in process design like they do for product design.

Building quality into business processes is about the fundamentals — robust design and visual management (what makes any generic business process stop when quality is unacceptable).

Poka-Yoke is absoutely the way to go for newly-created processes, or as an solution for already-created processes but are producing defects. For mature firms, however, there exists processes, methods, tribal knowledge, and culture, that need help. Yes, prevent errors through mistake-proofing; for processes that have already been engineered but are producing defective products — that was really the point of this article.

The goal of zero defects can be achieved through Error Proofing devices or methods. The most clever error proofing methods are inexpensive — think things like a template bar that prevents a too-tall vehicle from driving into a parking garage when it wouldn’t have fit. Error Proofing methods are more cost effective than traditional defect prevention methods, such as inspection or telling employees to “be careful or you’re fired.”

Fundamentally, it needs to be appreciated that there is a difference between reducing defects and eliminating them. The cost of trying to support zero defects goes up exponentially as you get closer to zero. Deming used the red bead experiment to highlight that if a process has a failure rate built into it from the beginning, worker competence is not the issue. It really is all about management.

Rob

I certainly will never institute such a policy at my current employer for our developers. To work towards approaching zero (regardless of whether that number is 10, 100, 1000 or whatever is right for the resources you have at hand and the value it delivers to the business) is a much better approach in practice.

It wont surprise you that my previous employer is no longer operating…