I never remove slot cards that are inserted into the machine.... many times a nearby player could be playing multiple machines. There are simply lots of them laying on top of the machine where either the slot attendant (if he/she isn't on strike ) will remove "dead cards" and place them on top of the machines or a player who wants to play a particular vacant machine removes the left behind card to insert her/his own player's card. Of course it helps if one is 6 foot tall to spot them on top of the machines Jim.