Books have been set forth on this issue, and the bickering and disharmony about where the "hot" slots are installed in the casino are still on-going – sixty years after one armed bandits were first added to the gaming floor in the casinos.
The quintessential rule is that the more favourable slot games were placed just inside the door of the casino; so that persons going by would be able to see real jackpot winners and be captivated to come unto the gambling floor and play. Our deduction is that this is not so anymore.
Practically all of the large casinos nowadays are magnificent complexes … it is not possible to see inside from the sidewalk, so there’s no longer a reason to situate the ‘loose’ slot games close-by any doorways.
Another traditional rule is that loose slot machines are put on the major aisles in the casinos, again so that more folks could see winning jackpots and be roused to play. Importantly however, 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 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.