Books have been said on this subject, and the debates and ruckus about where the "hot" slot games are located in a casino are still ongoing – 60 years after one armed bandits were first added to the gaming floor in gambling dens.
The traditional rule is that the superior one armed bandits were located just inside the entrance of the casino; so that persons passing by would see jackpot winners and be baited to come inside … play. Our observation is that this is not so anymore.
The majority of the major casinos presently are massive complexes … you can no longer see inside from the sidewalk, so there’s no longer a reason to position the ‘loose’ one armed bandits close to any exits.
An additional classic rule is that loose slots are installed on the major aisles inside the casinos, again so that more persons could see winning jackpots and be energized to play. Importantly however, we find that this also is not 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 slot games 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 perspective about where to place the loose slot games.