I requested PTO to attend a family wedding. My boss approved. While I was out on PTO, during an exec meeting, the CEO asked my boss about the status of the project I was on. Boss forgot or neglected to mention I was on PTO, and the CEO reminded him of that, and my boss was pissed that he looked foolish.

The day I returned, I was called into a meeting with HR and my boss, and berated for going on vacation without informing my boss (who again, approved my PTO), nor informing my team (a categorical lie). Later, my position was eliminated.