" Psychologists often make a distinction between mistakes where we already know the right answer and mistakes where we don’t. A medication error, for example, is a mistake of the former kind: the nurse knew she should have administered Medicine A but inadvertently administered Medicine B, perhaps because of confusing labeling combined with pressure of time. But sometimes mistakes are consciously made as part of a process of discovery. Drug companies test lots of different combinations of chemicals to see which have efficacy and which don’t. Nobody knows in advance which will work and which won’t, but this is precisely why they test extensively, and fail often. It is integral to progress. "

― Matthew Syed , Black Box Thinking: Why Some People Never Learn from Their Mistakes - But Some Do