Books have been said on this subject, and the conflict and squabbling about where the "hot" slot games are located in a casino are still happening – more than 60 yrs after slots were 1st installed in the casinos.
The quintessential rule is that the best slot games were installed just inside the entrance of the casino; so that persons going by would be able to see actual jackpot winners and be aroused to come into the casino and play. Our persuasion is that this is definitely no longer true.
Nearly all of the large casinos today are giant complexes … it is not possible to see inside from the sidewalk, so there is no longer a reason to place the ‘loose’ slots close-by any entrances.
Yet another standard rule is that loose one armed bandits are put on the major aisles inside the casinos, again so that more potential players could see winning jackpots and be roused to play. Notably though, 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 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 slots.