Books have been said on this matter, and the controversy and arguments about where the "hot" slots are positioned in a casino are still intense – more than 60 years after the slot machines were 1st placed in casinos.
The classic rule is that the most favorable slot games were installed just inside the door of the casino; so that everyone walking by would see real jackpot winners … be intrigued enough to come inside and play. Our observation is that this is definitely no longer so.
Many of the mega casinos today are immense complexes and you no longer can see inside from the sidewalk, so there is no longer a reason to position the ‘loose’ slot machine games close to any doorways.
Yet another standard rule is that loose slots are located on the major aisles in the casinos, again so that more potential gamblers could see winning jackpots and be galvanized 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 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 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 philosophy about where to place the loose slot games.