Books have been written on this item, and the bickering and disagreement about where the "hot" one armed bandits are installed in the casino are still ongoing – over sixty yrs after slot machines were 1st installed in gambling houses.
The classic rule is that the most favorable slot games were located just inside the entrance of the casino; so that fun seekers going by would be able to see jackpot winners … be enticed to come unto the gambling floor … play. Our attitude is that this is no longer the case.
Many of the major casinos today are massive complexes and it is not possible to see inside from the sidewalk, so there’s no longer a reason to have the ‘loose’ slots in close proximity to any entrances or exits.
An additional standard rule is that loose slot machines are installed on the major aisles in the casinos, again so that more people could see winning jackpots and be galvanized to play. Interestingly though, 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 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!
Nowadays, casinos are constantly changing their perspective about where to place the loose one armed bandits.