Corporations value consistency over correctness. Your manager is your manager because the company trusts him. Even if the evidence suggests strongly that your boss is in the wrong, the best you're likely to get is a pyrrhic victory: the boss goes down, but so do you.
It takes a whole-team revolt to beat a bad boss through HR channels, and most people aren't willing to put their careers at risk. Not only that, but after you beat a bad boss, you're still viewed with suspicion by managers ("protect our own") and will have a hard time getting a transfer or promotion.
It takes a whole-team revolt to beat a bad boss through HR channels, and most people aren't willing to put their careers at risk. Not only that, but after you beat a bad boss, you're still viewed with suspicion by managers ("protect our own") and will have a hard time getting a transfer or promotion.