Some do. If they use their powers for personal gain, they risk losing them. If they use dark magic, they can change from being witches to being warlocks.
[She nodded a little.]
It's not related to men and women. Witch and warlock are good and evil where I'm from.
[She'd gotten turned once. They'd sort of let it happen to get Prue back, but she didn't really want to get into that.]