Volumes have been stated on this topic, and the disquiet and disharmony about where the "hot" slot games are placed in a casino are still bubbling – sixty years after slot games were 1st placed in gambling dens.
The quintessential rule is that the better one armed bandits were located just inside the door of the casino; so that potential players passing by would be able to see jackpot winners and be convinced to come into the casino and play. Our deduction is that this is no longer the case.
Many of the large casinos today are herculean complexes … you can no longer see inside from the sidewalk, so there is no longer a reason to position the ‘loose’ slot machines in close proximity to any exits.
Yet another classic rule is that loose slot games are placed on the major aisles in the casinos, again so that more people could see winning jackpots and be influenced to play. Notably 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!
Nowadays, casinos are constantly changing their philosophy about where to place the loose slot games.