Volumes have been set forth on this matter, and the bickering and discussion about where the "hot" one armed bandits are located in a casino are still on-going – 60 yrs after one armed bandits were first placed in gambling dens.
The quintessential rule is that the best slot machine games were put just inside the main doorway of the casino; so that casino fanatics passing by would see jackpot winners and be enticed to come into the casino and play. Our view is that this is definitely no longer the case.
Practically all of the major casinos these days are magnificent complexes … it’s no longer possible to see inside from the sidewalk, so there’s no longer a reason to put the ‘loose’ slot games near any doorways.
Yet another classic rule is that loose slot machines are positioned on the major aisles inside the casinos, again so that more folks could see winning jackpots and be influenced to play. Nonetheless, we find that this also is no longer a universal rule.
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 philosophy about where to place the loose slot machines.