Hmmm...typical.
You leave the boards a few days and what started as an innocent request for people's least favourite Prestige Classes degenerates into a debate on whether Prestige Classes should exist at all.
Not quite the original intention, but there we go.
My stance is that PrCs are interesting, and the thematics can be good, but the trick is not to be too restrictive.
A bad PrC IMO is one of the following:
1. Too strong (cos players will always take them)
2. Too weak (cos players will never take them- with a few exceptions. And you know the kind of people they are.)
3. Too narrow (you mean I can't be an Elite Arcane Battleaxe Knight of the Order of Gibbering Mouther Slayers?)
4. Too generic (Weaponmaster is often cited)
That was the sort of thing I was looking for, not a debate on PrCs altogehter. But there ya go.