Books have been said on this subject, and the contention and ruckus about where the "hot" one armed bandits are installed in the casino are still on-going – sixty yrs after slot machine games were first placed in gambling houses.
The standard rule is that the very best slot games were placed just inside the main door of the casino; so that folks walking by would see jackpot winners … be impressed enough to come unto the gambling floor … play. Our inference is that this is definitely no longer so.
Just about all of the major casinos presently are enormous complexes and it’s no longer possible to see inside from the sidewalk, so there is no longer a reason to situate the ‘loose’ one armed bandits near to any doors.
An additional classic rule is that loose one armed bandits are installed on the major aisles inside the casinos, again so that more potential gamblers could see winning jackpots and be energized to play. Importantly though, we find that this also is no longer a universal rule.
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!
Nowadays, casinos are constantly changing their philosophy about where to place the loose slot games.