I attended a meeting once where I disagreed with how my coworker was conducting it. Instead of gently redirecting the discussion or privately bringing up my concerns afterwards, I called the person a name right in front of everyone. It was an impulse to release some tension and perhaps shock my coworker into changing direction. I meant no real offense, but it was completely off-base for workplace communication and I derailed the whole meeting. The remaining conversation was awkward, tense, and unproductive.
Note to self: You can undo months' worth of work in seconds when you're not careful with how you interact with others.