Wrist cupped too much. Leaning too far forward at the line. You're throwing the ball with your forearm at the release rather than your arm/shoulder as a whole (which might be a result of your over-cupped wrist at release). You also speed up your steps as you progress the approach.

I would try to address them in this order:

Stop over-cupping the wrist, which may help with:

Releasing the ball with your forearm as opposed to your shoulder and entire arm. Think of this unit as a pendulum.

Then slow your footwork to be consistent which should stop you from:

Leaning forward too far at the foul line. You have so much momentum from those last two steps that your body is still moving towards the pins.




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There is nothing so easy to learn as experience and nothing so hard to apply.