Nylon - failure to appreciate failure

1935

Researchers in the early German polymer labs occasionally left a Bunsen burner lit over the weekend. Upon discovering this mistake on Monday mornings, the chemists simply discarded the overcooked results and went on with their day. Ten years later, Wallace Carothers, a chemist at DuPont made the same mistake. However, rather than simply discarding the mistake, he analyzed it and this led to the invention of nylon. If the German researchers had paid attention to their mistake, they might have had a decade head start in nylon and could have dominated the market for years. 

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Discover Magazine - The accidental inventor