Was an internal auditor translating department process to a technical spec for a programmer. We were going to leverage an external company's API which would replace our need to use their slow and buggy web app.

During a meeting, an audit teammate suggested something be changed with the external service we were using. I said we could bring it up with the company but we shouldn't rely on it because we were a small customer even during out busiest month (200 from us vs 10000+ from big banks).

Teammate said we should have our programming team fix it. I made it clear that it was not our side and that to build out the service on our side was beyond our scope. Teammate continued to bring it up during the meeting then went back to desk after meeting and emailed us all marked up screenshots of the feature.

I ignored this and finished writing up the specs, sending them over to the programmer building out the service.

30 minutes later I get a call from programmer's manager who was quite angry at an expanded scope that was impossible (engineers were king at this company. Best not to anger them). Turns out my teammate had emailed his own spec to the programmers full of impossible features that did not reference the API docs.

I feel bad about it now but I yelled at my teammate quite loudly. I said he was spending time on something that was not reasonable or possible and when they continued to talk about their feature I yelled even louder.

Didn't get fired but it definitely tagged me as an asshole until I left. Fair enough :)