Every project needs a combination of talents to succeed. I heard one commentator describe projects as needing a Hipster, Hacker and Hustler. Many of the early crypto products did and many current ones do not have enough of diversity in the talent pool.

Of course it comes down to your definition of success. I have no doubt that many projects are get rich quick schemes for the founders and the fact they are no longer around may indeed be a huge success for those people :)