Books have been stated on this matter, and the controversy and discord about where the "hot" slot machine games are positioned in the casino are still bubbling – 60 years after slot games were first installed in casinos.
The standard rule is that the better slot machine games were put just inside the main door of the casino; so that potential gamblers passing by would see real jackpot winners and be challenged to come unto the gambling floor and play. Our sneaking suspicion is that this is definitely no longer true.
Almost all of the major casinos today are grand complexes and you no longer can see inside from the sidewalk, so there’s no longer a reason to place the ‘loose’ slot machines near to any entrances or exits.
Another standard rule is that loose slot games are located on the major aisles in the casinos, again so that more potential players could see winning jackpots and be encouraged to play. Notably however, 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 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 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!
In recent times, casinos are constantly changing their philosophy about where to place the loose slot games.