Only thing I can think of is a long time ago being told if you hit this deadline here's £X thousand pound bonus for the team. We hit the deadline, they made me redundant next day and told me I wouldn't be getting my share because "you should have got it in writing"[0]
I took them to court and won eventually. Good fun.
[0] Which was a) true but b) plain nasty. Worth repeating at this point, the 3 laws of contracting:
1. Get it in writing
2. Get it in writing
3. Get it in writing