A person that cannot get fired from their current occupation no matter how below average or poorly they perform. The fact that this person is able to keep their job is incredible and leads others to believe he/she might be related in some way to owners or bosses or might be doing extra favors for them unknown to the public.
A: "Wow, how does this guy still have a job here? He has no skills and he actually brings our overall performance as a company down."
B: "No clue, we used to be a good company but with this Alex Smith on our team, we'll never get there again."