I'll admit in the corporate world it's a slow process to weed out any bad apples (pun not intended), but it does happen. There's accountability on every level.

I knew of a manager who wasn't very good, and once his directs escalated the issue, it was only a month or so until he was out the door.

There's also a sort of probation bad employees can be placed under, but I hear once you're in that boat, it's nearly impossible to get out from it.