once the defense makes a move toward you. The holder puts his hand up, which tells the long snapper he is ready. Then the snapper snaps the ball ideally at a random time so teams don’t try and time it by watching film.
Often times with false starts it’s a change in the count that throws off the team. Like going on two claps instead of one. Or in the case before the half, total miscommunication between the center not knowing Jake was all of a sudden going to be under center.