Severus Snape and Natasha Romanoff both did questionable things before then trying to make amends themselves. Did they do enough to redeem themselves?
Argus Filch is far from cuddly, but might he have some redeeming qualities?
It takes a painfully long time for the pompous Percy Weasley to come around – but he gets there in the end.
Draco Malfoy was raised to be a bully, but was there goodness underneath all along?