[clusmore]

I think it's really about how you define success and failure. For example, you have a great idea for a product and you decide to form a startup to build it. If you define success as "built the product and made lots of money", both outcomes "couldn't build it" and "built it but nobody wanted it" are considered failures. If you define success as "discovered whether or not this can be built, and whether it can form the basis of a viable business", then those two outcomes are considered successes.

Your goal should be to identify the major risks in whatever you're doing, and then set your success criteria to either confirm or overcome those risks as quickly/cheaply as possible. Failure is then only whether you spent too much time/money, not necessarily what the outcome was.