Books have been written on this subject, and the contention and discourse about where the "hot" slot games are placed in the casino are still ongoing – sixty yrs after slot machines were 1st placed in casinos.
The traditional rule is that the superior slot machines were installed just inside the door of the casino; so that individuals going by would be able to see real jackpot winners and be captivated to come unto the gaming floor and play. Our frame of mind is that this is no longer true.
The great majority of the major casinos today are massive complexes … you no longer can see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slot machines near any entrances.
Another classic rule is that loose slot machine games are installed on the major aisles in the casinos, again so that more potential players could see winning jackpots and be motivated to play. 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 very 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 games.