When are you being paid the right amount of money? Supply-and Demand would dictate that you are earning exactly what you are worth. If you are worth more, but you can’t figure out how to get the boss to pay you more or how to earn more; are you really worth more?
But I believe there is a better answer. Consider this scenario. If all salaries were made public (in your company) AND everyone got to vote on what everyone else should be paid, how much would you be earning? Would you have the confidence to put your salary to a democratic vote? Let’s be realistic and let us say only the subordinates (one level below), colleagues (peers) and superiors (one level above) could vote on what you should be paid, would you trust your colleagues to estimate your true worth accurately and reward you accordingly.
It is hypothetical of course – in the real world sycophants and spoilers would make something like that impossible, but at least it is a test that you can put to yourself and consider the answer honestly and fairly.
I very much doubt that many managers would get a salary increase.