Volumes have been written on this topic, and the contention and face-offs about where the "hot" slot machine games are positioned in the casino are still happening – over 60 years after the slots were 1st installed in casinos.
The classic rule is that the better slot games were installed just inside the door of the casino; so that potential gamblers passing by would be able to see jackpot winners … be attracted to come inside … play. Our estimation is that this is no longer true.
Many of the large casinos today are super-colossal complexes … now you can’t see inside from the sidewalk, so there’s no longer a reason to have the ‘loose’ slots near to any entrances.
Yet another standard rule is that loose slot machine games are placed on the major aisles in the casinos, again so that more persons could see winning jackpots and be motivated 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 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!
Nowadays, casinos are constantly changing their philosophy about where to place the loose slot machines.