Volumes have been set forth on this issue, and the conflict and feuds about where the "hot" slot machine games are installed in a casino are still taking place – 60 years after the slot machines were first added to the gaming floor in gambling houses.
The classic rule is that the most favorable slots were put just inside the main entrance of the casino; so that persons going by would see jackpot winners and be drawn to come unto the gambling floor … play. Our reckoning is that this is definitely no longer so.
Many of the major casinos today are monstrous complexes and it is not possible to see inside from the sidewalk, so there’s no longer a reason to position the ‘loose’ slot machines near any exits.
Another traditional rule is that loose slot machine games are put on the major aisles inside the casinos, again so that more potential gamblers could see winning jackpots and be motivated to play. Importantly 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 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!
Today, casinos are constantly changing their perspective about where to place the loose slot machine games.