[The Yen Man]

Everyone thinks they're a rock star and underappreciated by their company. The thing I learned a long time ago is that no individual person is irreplaceable in a company. A lot of people have this attitude of "oh, just wait until I quit. They'll be screwed without me". News flash. The company was there before you, it will be there after you're gone.

I've done performance reviews where the employee thought they were awesome, pointed out some stuff they should work on, and have them get all defensive.