Someone very smart told me that incompetence is a form of bias all of its own, because it privileges people who are able to ask for corrections in their favor.

(They had a nice worked example involving exam results - some years have much higher variance than others, due to incompetence in question-setting or marking, and in those years the mis-marking is randomly distributed but only the more middle class parents manage to work the system to get re-marked)

This is such a dangerously naïve view. Anyone who's any good at all at politics has learnt that this heuristic is widely applied, and is therefore careful to make a huge fuss irrespective of how well or badly things are going for them.

(Well, I say anyone; I guess I mostly mean bad people, who aren't restrained by fairness or honesty).