Was once a senior engineer at a small-ish office of a fairly large company. We had a particularly high-strung junior engineer that was prone to throwing fits if he didn't get his way.

Apparently, one day, he threatened to quit for another offer. He was placated with some trivial pay increase and promotion to lead engineer (essentially leap-frogging the other seniors in the office in title - but not in pay).

Except no announcement was made; I had no idea he'd been promoted. One day he walks into my office and starts telling me I need to redesign some module using XYZ Design pattern.

"Nope, don't think so - that would be a pointless and unnecessary complication and we have a release on Friday."

"No, you need to do it. I already talked to the Engineering Manager."

I can't remember exactly what I said next, but it wasn't very nice.*

Then I'm getting called into the Engineering Manager's office: "Can you just do the thing he asked you to do, please? I know, I know... we kinda have to humor him on this."

* - of course I remember what I said, and it definitely wasn't nice.