Because HR is in on it as well.They are worse than the managers.Caniving pieces of shit.They look for reasons to fire you and if they don't like you or if your views differ than theirs, out comes the PIP....Thats how they get rid of people they don't like or those that conform to their fucked up culture. They are left winged Marxists headquartered in Cally so if you are a conservative and believe differently politically, you might want to keep it that to yourself or risk getting fired.
