Books have been said on this topic, and the debates and discussion about where the "hot" slots are located in the casino are still taking place – sixty years after slot machine games were 1st placed in gambling houses.
The standard rule is that the most favorable slots were installed just inside the main door of the casino; so that potential gamblers going by would see actual jackpot winners and be impressed enough to come inside … play. Our theorem is that this is no longer true.
Nearly all of the big name casinos today are jumbo complexes … you no longer can see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slot machine games in close proximity to any of the doors.
An additional traditional rule is that loose slot machines are positioned on the major aisles inside the casinos, again so that more fun seekers 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 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!
These days, casinos are constantly changing their philosophy about where to place the loose slot machine games.