Your just missing the shot.
Or your aim is off for the loop.
Quoted from WizardsCastle:I'm getting loads of shots up the right ramp, that roll back down and SDTM.
Most come from the upper flipper missing the loop and going up the ramp, but also some of the fly shots that just don't have enough juice end up rolling back down and draining.
Is this the design of the game, or is mine off?