Volumes have been said on this matter, and the disquiet and disagreement about where the "hot" slot machines are installed in the casino are still taking place – 60 yrs after slot machines were 1st installed in casinos.
The quintessential rule is that the superior one armed bandits were installed just inside the main entryway of the casino; so that potential gamblers walking by would be able to see real jackpot winners and be influenced to come into the casino and play. Our interpretation is that this is not so anymore.
Most of the big name casinos presently are immense complexes … now you can’t see inside from the sidewalk, so there’s no longer a reason to have the ‘loose’ slot machines close-by any exits.
An additional traditional rule is that loose slot machines are installed on the major aisles in the casinos, again so that more persons could see winning jackpots and be energized to play. Notably however, we find that this also is no longer a universal rule.
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 one armed bandits 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 very 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!
These days, casinos are constantly changing their perspective about where to place the loose slot machines.