Books have been written on this matter, and the debates and squabbling about where the "hot" slot games are positioned in the casino are still bubbling – over 60 years after slot machine games were 1st added to the gaming floor in gambling houses.
The traditional rule is that the better slot machine games were installed just inside the door of the casino; so that potential gamblers passing by would be able to see actual jackpot winners and be smitten to come unto the gaming floor and play. Our theory is that this is definitely no longer so.
The great majority of the big name casinos presently are behemothic complexes … now you can’t see inside from the sidewalk, so there’s no longer a reason to have the ‘loose’ slot machine games in close proximity to any entrances or exits.
An additional classic rule is that loose slots are located on the major aisles in the casinos, again so that more potential gamblers could see winning jackpots and be galvanized to play. Notably 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 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 philosophy about where to place the loose one armed bandits.