Most of mine were 2nd round guys (I have 2 or 3 a year that I become a little too attached too lol) so not necessarily sure you can call them fails.
Richard Howell, Norris Cole, Trevor Mbakwe Lorenzo Brown, David Lighty, Armon Johnson were all guys I thought would be nba role players at worst.
I've actually been pretty happy with my evaluations on 1st round guys. Most of the guys that I've really liked, even as late as late lotto to mid first, have stuck as starting quality players (McCollum, Adams, Markieff Morris, Gorgui Deing, Jimmy Butler to name a few)
The two that stick out as guys I was little to high on was Alec Burks (he has had a lot of injuries though), and Jared Sullinger (Thought he could be a Love type w/o the passing) .