Books have been set forth on this matter, and the conflict and discussion about where the "hot" slot machine games are positioned in a casino are still rampant – 60 years after slot machines were 1st placed in casinos.
The quintessential rule is that the best slot machines were located just inside the door of the casino; so that potential players passing by would see real jackpot winners … be challenged to come inside and play. Our view is that this is definitely no longer the case.
Almost all of the mega casinos these days are giant complexes … now you can’t see inside from the sidewalk, so there’s no longer a reason to situate the ‘loose’ slot machines close-by any entrances or exits.
Another standard rule is that loose slot games are positioned on the major aisles inside the casinos, again so that more potential players could see winning jackpots and be influenced to play. Nonetheless, 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 the slot machines 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 very 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!
These days, casinos are constantly changing their perspective about where to place the loose one armed bandits.