A location with a history of games being broken into, that is large, can be hard to watch everything.
So the op will wire up games so if the door is pried open or anything, an alarm goes off there or at a counter or office in the building.
They usually wire them all together. Game to game to game back to where people might hear the alarm. Then in theory they go running around to find what set it off and catch the criminal.
What usually happens is they find nothing wrong, turn alarm off, and go back to work. Then when they are in another part of the building, the perpetrator returns and cleans out the cash box, or just takes the whole game. ( 2001 pinball machine, Maplewood Bowl 1972 )..
LTG : )™