Books have been stated on this subject, and the debates and squabbling about where the "hot" one armed bandits are installed in the casino are still bubbling – over 60 yrs after slot machines were 1st placed in gambling houses.
The classic rule is that the very best one armed bandits were placed just inside the entry of the casino; so that folks passing by would be able to see real jackpot winners and be challenged to come unto the gambling floor … play. Our sneaking suspicion is that this is not so anymore.
The majority of the major casinos today are grand complexes … it is not possible to see inside from the sidewalk, so there is no longer a reason to put the ‘loose’ slots near any doors.
Another traditional rule is that loose slot machine games are put on the major aisles inside the casinos, again so that more potential players could see winning jackpots and be roused to play. Importantly though, we find that this also is not 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 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!
Nowadays, casinos are constantly changing their philosophy about where to place the loose one armed bandits.