Nothing infuriates me more than when a mod deletes or modifies someones post without a pm to that person explaining why the action was necessary / taken - or even a reason put in the place of the 'offending' post.
I am a mod / supermod elsewhere and have been on the receiving end of such actions - banned in some cases with the infuriating situation of having no access for redress.
Mods have to be as impartial as it is possible to be. I have seen my posts withdrawn / deleted and the mod concerned (not here I may add) has admitted they didn't bother to read the whole post - merely the 1st line. Got their knickers in a total twist by misinterpreting a post from one word in the 1st line. Modship sadly goes to the heads of some people.
PS - don't ask me to mod - I am not on here often enough!!