Books have been said on this topic, and the disquiet and ruckus about where the "hot" one armed bandits are located in a casino are still passionate – sixty yrs after the slots were 1st placed in gambling dens.
The traditional rule is that the most favorable slot machines were put just inside the entrance of the casino; so that individuals passing by would be able to see jackpot winners and be possessed to come into the casino and play. Our position is that this is not so anymore.
Many of the large casinos these days are magnificent complexes … you no longer can see inside from the sidewalk, so there is no longer a reason to put the ‘loose’ slot machine games near any doors.
An additional standard rule is that loose slot games are placed on the major aisles in the casinos, again so that more fun seekers could see winning jackpots and be galvanized to play. Nonetheless, 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 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 slots.