Books have been written on this issue, and the conflict and disagreement about where the "hot" slots are placed in the casino are still happening – 60 years after slot machines were first added to the gaming floor in casinos.
The traditional rule is that the more favourable slots were put just inside the main entry of the casino; so that everyone walking by would see jackpot winners and be aroused to come unto the gaming floor … play. Our inference is that this is no longer true.
Just about all of the large casinos nowadays are colossal complexes and now you can’t see inside from the sidewalk, so there’s no longer a reason to place the ‘loose’ slot machine games near any doors.
Another traditional rule is that loose slot games are placed on the major aisles inside the casinos, again so that more potential gamblers could see winning jackpots and be roused to play. Notably however, we find that this also is not 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 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 perspective about where to place the loose slot games.