Books have been written on this matter, and the conflict and ruckus about where the "hot" slot machine games are located in a casino are still there – sixty yrs after slot games were first installed in gambling houses.
The classic rule is that the most favorable slot machine games were placed just inside the main entry of the casino; so that persons passing by would be able to see jackpot winners … be infatuated enough to come unto the gaming floor … play. Our observation is that this is definitely no longer so.
Most of the big name casinos presently are monstrous complexes and it is not possible to see inside from the sidewalk, so there’s no longer a reason to place the ‘loose’ slot games in close proximity to any entrances or exits.
Yet another classic rule is that loose slot games are located on the major aisles in the casinos, again so that more potential players could see winning jackpots and be influenced to play. Notably 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 slot machine 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!
In recent times, casinos are constantly changing their perspective about where to place the loose slot machine games.