Every ref makes a bad call now and again and every participant and/or fan is able to forgive it based on the fact that most refs know they made a bad call, and while they may not reverse the call, they usually are more aware and do not repeat the mistake OR they make it up to the wronged wrestler in other calls. There are really only 2 times the bad calls are really hard to forgive.
1. When it is the final call that decides the winner.
2. When the ref becomes defensive and repeats the bad call over and over as if to prove his point...

The best ref is the one you can't remember because he did not make himself a participant in the match, just an objective observer.