Pay increase or leave

If you hold a company to ransom and more specifically a particular manager, you can expect two things, they will do their best to make sure you can't put them into that situation again down the line and the minute they don't need you, your stock will plummet and perhaps they will actively manage you out. So you better have a plan B to whip out of your pocket.

And if you do try to use exit as a bargaining tool you need to be prepared if they decide to take you up on your offer. I can remember one very cockey individual telling us how he was going to get a salary increase going into a meeting with his manager.... he should have copped on when the manager brought his deputy (as a witness?) that the game was up.... twenty minutes later he was clearing out his desk under the supervision of a security guard. Seems he talked himself into a resignation which was accepted on the spot, with no need to work out the notice period.