Imo a kick/ban poll should be started only if a player is teamhitting/teamkilling on purpose, if you can't stand that someone is insulting you, just mute him.
Ppl often start polls for silly reasons, and they don't realize that polls are a pain in the ass, because no one likes when a "wall of text" appears in the middle of the screen (expecially when the enemy players are trying to hit your char) .
You should give a reason before starting a poll, and if you really want to kick/ban poll someone, start a a poll at the beginning of the round.
Imo insulting is not a valid reason to kick/ban poll someone.