Among Catherine Conlan’s "5 Things You Should Never Say at Work" are two that apply particularly to all varieties of Bad Boss, because Bad Bosses, regardless of their type, routinely ignore job descriptions and duties in favor of their own whims or (often irrational) desires.
So you will undoubtedly find yourself saying at one time or another:
It's not fair. Whether this is true or not, this is one of the most unhelpful things you can say at work. No matter how you say it, it's going to come across as whining. And the answer you're likely to get can be something along the lines of "You're right -- so what?" Instead, find more concrete, fact-based objections to something you want to change, rather than relying on emotional appeal.
That's not my job. In today's work environment, employees are often asked to go above and beyond as a matter of routine. "That's not my job" can make you look stubborn, lazy and generally uninterested in the company's success. Instead, identify the problem you have with the task at hand -- is it something you truly don't have time for? Is it something that someone else would do better?
When you hear yourself protesting "It's not fair/not my job" - think! Get creative. Use your imagination. Somewhere in what is being asked of you is something you can turn to your advantage.
That’s what is important here. Your career, your success. Every successful person has had to deal with unfairness of one type or another, yet it’s learning to deal constructively with those unfairnesses that often has contributed significantly to their career.