We have all tripped. You weren't expected the next stair-step to be that high. You didn't think that the tile floor would have a raised tile. You hadn't considered that a bunch of wet shoes would be lounging in the middle of a dark room. You weren't looking at where you were going, but your feet found a thick line on the basketball court. No one is immune to the occasional clumsiness.
But have you ever seen someone trip and look back with utter disgust. They look back like they are going to take a jackhammer/knife/Mr. T/prison guard to that whatever just tripped them. It is hilarious.