A good firm grip and bad wrist angle will twist the bow in your hand when you release the string. That means as the arrow is traveling forwards, it is also being pushed sideways towards your bow arm. That, in effect, exaggerates the paradox the arrow has to correct for.
I was frustrated for ages with wrist slap, fiddling with brace height, trying to build bows more and more centershot. Turns out I needed to take the advice of the 80's southern rock band, 38 Special....hold on loosely, and don't let go, if you cling too tightly to her, you gonna lose control.