Quoted from Meloyelo51:what I refer to as an "autosave" where you get the ball back in the shooter lane, however it only works if it is a super fast drain, does not touch a single target/switch, and I want to say also player not hitting the flipper buttons.
That is “playfield validation”. Typically a table will not end the ball until three switches are hit. The thinking is there was probably an error and somehow the ball didn’t get played. Modern games often have specific switches that validate the playfield automatically no matter how many switches have been hit.
Cayle George is legendary for figuring out playfield validation exploits.