The "bane" of all archers!!! Seems that everyone develops it at some time, and occasionally it can be very hard to get rid of. It is the archer's equivalent of "flinching" that the gun shooter might develop, because of anticipation of the recoil! Some forms it may take, are the pins seemingly "freezing" under your target, and not being able to put the pin on the target, or perhaps premature "punching"(rather than the gentle pressure, and "expected" release) from the properly executed mechanical or finger bowstring release. Lots of concentration, and perhaps "closed eye" blind bale shooting, just concentrating on form will cure you of it.