1. It's not just that they don't pay you enough, it's that they couldn't ever pay you enough to make you feel good.

People who feel underpaid always think that more money will make them feel better. Sometimes it will, but sometimes it won't. And I can prove it. If your biggest complaint about your job is the salary, consider whether an amount 10 percent higher would make you happy. Then think of a number that is 20 percent higher. If a 10 to 20 percent increase would make you feel well compensated, you're in the right job—you just need to work on getting a raise. If you could go as high as 50 to 100 percent more and still not be satisfied, then money isn't the problem and more of it won't make you feel better. It's time to find another position within the company or a new job altogether.