Happens when one of a couple of things occur.
Both things involve the meter power being far left or far right. In both cases the ball doesn't move but you will hear a swinging sound.
Way left would be hitting the screen/mouse or being too close to screen so that it reads a touch right after releasing the swing.
Way right is result of having either a skippy meter so you let the meter go to the end then you touch the screen before the screen resets so it reads the "hit".
the latter can also occur if you try to tap and miss screen and let the power bar go to the end.
let the screen reset if you do that.