Books have been stated on this matter, and the debates and feuds about where the "hot" slot games are placed in a casino are still intense – over sixty years after slot games were 1st installed in gambling houses.
The standard rule is that the very best slots were put just inside the entry of the casino; so that people passing by would see actual jackpot winners and be possessed to come inside … play. Our deduction is that this is not so anymore.
Most of the large casinos these days are titanic complexes … it is not possible to see inside from the sidewalk, so there’s no longer a reason to put the ‘loose’ slots near any entrances or exits.
Another classic rule is that loose one armed bandits are positioned on the major aisles in the casinos, again so that more persons could see winning jackpots and be motivated 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 slot games 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!
In recent times, casinos are constantly changing their perspective about where to place the loose slots.