Volumes have been said on this matter, and the contention and ruckus about where the "hot" slot machine games are installed in a casino are still happening – over 60 years after slots were first added to the gaming floor in casinos.
The quintessential rule is that the best slot machines were installed just inside the main entryway of the casino; so that casino fanatics passing by would be able to see real jackpot winners … be influenced to come into the casino and play. Our resolution is that this is definitely no longer so.
The majority of the large casinos today are colossal complexes … you no longer can see inside from the sidewalk, so there is no longer a reason to position the ‘loose’ slots close to any doors.
An additional classic rule is that loose slot games are positioned on the major aisles in the casinos, again so that more potential gamblers could see winning jackpots and be galvanized to play. Importantly 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 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!
Nowadays, casinos are constantly changing their philosophy about where to place the loose slot machines.