Books have been said on this matter, and the debates and disagreement about where the "hot" slot machine games are placed in a casino are still taking place – sixty years after slots were first placed in gambling houses.
The standard rule is that the better slot machine games were placed just inside the entrance of the casino; so that casino fanatics passing by would see actual jackpot winners and be aroused to come unto the gambling floor … play. Our presumption is that this is not so anymore.
Nearly all of the major casinos presently are humongous complexes … it’s no longer possible to see inside from the sidewalk, so there is no longer a reason to place the ‘loose’ slot games close to any doorways.
Yet another traditional rule is that loose one armed bandits are positioned on the major aisles in the casinos, again so that more fun seekers could see winning jackpots and be galvanized to play. Interestingly though, we find that this also isn’t 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!
Today, casinos are constantly changing their perspective about where to place the loose slots.