Fumbles are one of the dumbest plays in football. One second world class athletes are computing complex schemes in their head to execute assignments with a level of athleticism the average viewer wishes they had. The next second those same 22 players are clumsily diving on the ground trying to a grab ball with two points on it that causes the most unpredictable type of bounces of any type of athletic piece of equipment.
There are two aspects to a fumble.
1. The ever fumble happening. The Occurrence of a fumble
2. Recovering the fumble. The Recovery of a fumble
Occurrence
The occurrence of a fumble is a matter of skill and performance.