I refuse to believe this is an actual minhag with any basis in anything real or holy.
As far as I know, chassidim, same as the rest of us, are born with a yetzer hara, and get a yetzer tov when it’s time for them to start behaving like good Jews who take responsibility for their actions. And as is the case with the rest of us Yidden, the two both have great influence on their actions.