Books have been written on this topic, and the disquiet and face-offs about where the "hot" slot machine games are installed in the casino are still ongoing – more than 60 yrs after the slot machines were first added to the gaming floor in the casinos.
The classic rule is that the more favourable one armed bandits were put just inside the main foyer of the casino; so that people going by would be able to see jackpot winners and be smitten to come into the casino … play. Our assessment is that this is no longer the case.
The majority of the mega casinos today are jumbo complexes and now you can’t see inside from the sidewalk, so there’s no longer a reason to position the ‘loose’ slot machine games close-by any doors.
Yet another traditional rule is that loose slot games are installed on the major aisles in the casinos, again so that more persons could see winning jackpots and be energized to play. Importantly 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 the slots 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 machines.