I think what really feels great is financial freedom. When you are dependent on that next paycheck, you are understandably more likely to put up with things and less likely to complain. Now that I am working in an encore career strictly by choice, I do feel more empowered to speak out.

Also, it depends on the boss -- I have always gauged which ones will respect me if I criticize them, versus those who will feel threatened and become defensive or vengeful.