It's about time someone decided to debunk this awful bromide. Everyone who will fail (and succeed) conjures some personal lesson that is ill-derived, and eventually gets passed on as ambient, philosophical noise that people mistake for wisdom.(cough Brad Feld) You can only learn what not to do again from a failure, but a success gives you a recipe for future success, at least to a certain degree. At the end of the day, there are guidelines to follow, but everything is personal. Everyone has their own methods. You are respeonsible for your own pool of wisdom, and that requires building it from the ground up. I wouldn't say that an example of said pool that was constructed without any experience of failure is any worse than one built from success.