Volumes have been stated on this topic, and the controversy and disagreement about where the "hot" slot machines are positioned in a casino are still taking place – sixty years after the slot machines were 1st added to the gaming floor in gambling dens.
The classic rule is that the best slot machines were located just inside the main door of the casino; so that everyone passing by would be able to see real jackpot winners and be tempted to come unto the gambling floor and play. Our estimation is that this is definitely no longer the case.
Many of the large casinos nowadays are colossal complexes … you no longer can see inside from the sidewalk, so there is no longer a reason to place the ‘loose’ slot machines near to any entrances or exits.
Yet another standard rule is that loose slots are located on the major aisles in the casinos, again so that more potential players could see winning jackpots and be influenced to play. Nonetheless, 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 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!
These days, casinos are constantly changing their philosophy about where to place the loose one armed bandits.