five or six attempts to get a product right (Donald Norman)

 
 •─ It usually takes five or six attempts to get a product right. 


Donald A. Norman, The psychology of everyday things, 1988             [ ]

In Don Norman's wonderful book "The Psychology of Everyday Things" (now called "The Design of Everyday Things" in paperback)

p.29
  It usually takes five or six attempts to get a product right. This may be acceptable in an established product, but consider what it means in a new one. Suppose a company wants to make a product that will perhaps make a real difference. The problem is that if the product is truly revolutionary, it is unlikely that anyone will quite know how to design it right the first time; it will take several tries. But if a product is introduced into the marketplace and fails, well that is it. Perhaps it could be introduced a second time, or maybe even a third time, but after that it is dead: everyone believes it to be a failure.
  I asked him to explain. “You mean,” I said, “that it takes 5 or 6 tries to get an idea right?”
   “Yes,” he said, “at least that.”
   “But,” I replied, “you also said that if a newly introduced product doesn't catch on in the first two or three times, then it is dead?”
   “Yup,” he said.
   “Then new products are almost guaranteed to fail, no matter how good the idea.”
   “Now you understand,” said the designer. “Consider the use of voice messages on complex devices such as cameras, soft-drink machines, and copiers. A failure. No longer even tried. Too bad. It really is a good idea, for it can be very useful when the hands or eyes are busy elsewhere. But those first few attempts were very badly done and the public scoffed--properly. Now, nobody dares try it again, even in those places where it is needed.”

    (Norman, Donald A., The psychology of everyday things, 1. design, industrial--psychological, aspects, 2. human engineering, copyright © 1988, 620.82 Norman, p.29)
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