When I was 15 years old my friends and I used to play soccer and to learn how to give direction to the ball, we would try to hit the crossbar, if we don’t hit the crossbar we would have to stay in front of the goal post and the one who hit the crossbar, would shoot the ball trying to hit the one that did not hit the crossbar.
The reinforcer was being hit with the soccer balls
The response was to give the exact direction and force to hit the crossbar
This is an example of a negative reinforcement, because to avoid