Books have been written on this item, and the disquiet and interchanges about where the "hot" one armed bandits are positioned in a casino are still taking place – sixty years after slot machines were 1st installed in gambling dens.
The classic rule is that the best slot machines were put just inside the main foyer of the casino; so that folks walking by would be able to see actual jackpot winners and be convinced to come unto the gaming floor and play. Our theory is that this is no longer the case.
Most of the large casinos presently are immense complexes and it’s no longer possible to see inside from the sidewalk, so there is no longer a reason to position the ‘loose’ one armed bandits in close proximity to any entrances or exits.
An additional standard rule is that loose slot machines are located on the major aisles inside the casinos, again so that more potential gamblers could see winning jackpots and be galvanized to play. However, 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 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 perspective about where to place the loose one armed bandits.