Books have been stated on this matter, and the contention and discord about where the "hot" slot games are placed in the casino are still on-going – over sixty yrs after one armed bandits were first installed in the casinos.
The standard rule is that the better slot games were installed just inside the main entry of the casino; so that fun seekers going by would be able to see real jackpot winners … be challenged to come into the casino and play. Our reasoning is that this is not so anymore.
Most of the large casinos these days are titanic complexes … it is not possible to see inside from the sidewalk, so there is no longer a reason to situate the ‘loose’ slot machines in close proximity to any doors.
Yet another classic rule is that loose one armed bandits are placed on the major aisles in the casinos, again so that more fun seekers could see winning jackpots and be encouraged 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 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 one armed bandits.