Books have been written on this subject, and the contention and discourse about where the "hot" slot machines are positioned in the casino are still raging – more than 60 yrs after slots were first placed in casinos.
The quintessential rule is that the best one armed bandits were located just inside the main entryway of the casino; so that individuals passing by would see actual jackpot winners … be impressed enough to come into the casino and play. Our determination is that this is definitely no longer true.
Almost all of the major casinos today are enormous complexes … it is not possible to see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slots near any exits.
Yet another standard rule is that loose one armed bandits are placed on the major aisles in the casinos, again so that more potential gamblers could see winning jackpots and be inspired to play. Interestingly though, 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 the slot machines 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!
Nowadays, casinos are constantly changing their philosophy about where to place the loose slot machine games.