Why do managers believe they can be rude

I've experienced, and have witnessed, managers being rude and unprofessional to their direct reports, but if the shoe was on the other foot then all hell would break loose. I manage a team and have never been rude to any of them, things go wrong and hard conversations sometimes need to happen, but it's always been respectful. I really don't understand how people think they are entitled to behave that way. And after they're done and walk away, how they self justify it instead of feeling like a low life for treating people they rely on so poorly.

Posted by /u/MooseKnuckleds on r/jobs
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