Books have been written on this matter, and the contention and discourse about where the "hot" slot machine games are installed in the casino are still passionate – more than sixty yrs after the slot machines were first added to the gaming floor in casinos.
The quintessential rule is that the superior slot machines were located just inside the main door of the casino; so that everyone passing by would be able to see actual jackpot winners and be convinced to come into the casino and play. Our assurance is that this is definitely no longer the case.
Nearly all of the large casinos today are monstrous complexes … it is not possible to see inside from the sidewalk, so there is no longer a reason to position the ‘loose’ slot games near any doors.
Another traditional rule is that loose slots are placed on the major aisles inside the casinos, again so that more folks could see winning jackpots and be galvanized to play. However, we find that this also isn’t a universal rule any more.
What casinos found over the years is that people walking down the busy aisles were frequently on the way to somewhere else. If they played slots at all, they would simply put in their loose change because they happened to be walking by. Win or lose, they would very often not stop to keep playing. And the last thing a casino wants is for someone to win a jackpot by playing only a few coins and then not stay to put it all back in!
Today, casinos are constantly changing their philosophy about where to place the loose one armed bandits.