I was present when a few blokes were trying to drag a 4x4 out of a bog which had a fairly steed incline.
One driver pulled up rear first with his 4x4 and proceeded to run out the cable, hooked it to the proper anchor points of the bogged machine and then hooked the other end to his tow ball.
As the tension grew and the bogged 4x4 was going nowhere the tow ball snapped off the pulling 4x4 and went straight through the front windshield and out the back window of the bogged vehicle, missed the driver by centimeters .

can you imagine the tension on that cable, like a rubber band.
Wow scary stuff, this procedure has actually killed people.
Leon