We're signing "rough diamonds" if their character is right.
I would question the idea that Morrison is a rough diamond at all though. The mythology around him seems to come from an anecdote that Fergie thought he was the most talented players he'd sign at a young age. But the comment came from Rio Ferdinand, not Fergie directly and Fergie thought he was so talented, that he never played a league match for Man Utd and was gone by the time he was 19. Since then he's had 12 clubs and I'm not aware that he's massively impressed at any of them.