Maybe crying is a means of cleaning yourself out emotionally. Or maybe it's your last resort; the only way to express yourself when words fail, the same as when you were a baby and had no words.
When I'm crossing the street, I look both ways and I process the information rationally because if I make a mistake I get hurt, but when I cast a vote, kind of regardless of how I voted, doesn't make a difference and that's sort of a recipe for uninformed and irrational voting.