Books have been written on this matter, and the controversy and feuds about where the "hot" one armed bandits are installed in a casino are still passionate – more than 60 years after slot games were first installed in gambling houses.
The standard rule is that the better one armed bandits were placed just inside the main doorway of the casino; so that people going by would be able to see real jackpot winners … be influenced to come unto the gambling floor … play. Our attitude is that this is no longer the case.
The majority of the large casinos nowadays are huge complexes and now you can’t see inside from the sidewalk, so there is no longer a reason to situate the ‘loose’ slot machine games near any entrances or exits.
An additional traditional rule is that loose slot games are positioned on the major aisles inside the casinos, again so that more potential gamblers could see winning jackpots and be inspired to play. Interestingly though, 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 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 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 philosophy about where to place the loose slot machines.