Books have been stated on this subject, and the disquiet and discord about where the "hot" slot machine games are installed in the casino are still ongoing – more than 60 years after slots were 1st placed in gambling houses.
The traditional rule is that the most favorable slot machine games were put just inside the main entrance of the casino; so that individuals going by would see actual jackpot winners and be intrigued enough to come inside and play. Our interpretation is that this is definitely no longer the case.
Most of the big name casinos presently are behemothic complexes and now you can’t see inside from the sidewalk, so there’s no longer a reason to put the ‘loose’ one armed bandits near any entrances.
An additional traditional rule is that loose slot machine games are installed on the major aisles in the casinos, again so that more potential players could see winning jackpots and be galvanized 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 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 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.