I think my high-motor-skill son (12) is often refusing to play max performance (as his brothers often do) or even deliberate practice (when training) but trying out crazy things. I thought he was doing this out of spite or because he didn’t want to lose normally (his brothers are older). Maybe that was what got him into it initially. But whatever it was it leads him to try our things that sometimes work out so well that he keeps them.
Making very unusual motions (jumping, turning around) before shooting, kicking, serving.
Shooting (/kicking/serving) from extreme distances/angles.
Shooting with different parts of the foot/body.
Talking when you are not expected to do so.