Books have been stated on this subject, and the contention and disharmony about where the "hot" slots are installed in the casino are still on-going – 60 yrs after slot games were 1st added to the gaming floor in casinos.
The traditional rule is that the better slot machine games were positioned just inside the entrance of the casino; so that casino fanatics walking by would be able to see actual jackpot winners … be mesmerized enough to come inside and play. Our deduction is that this is not so anymore.
The majority of the mega casinos these days are colossal complexes … you can no longer see inside from the sidewalk, so there’s no longer a reason to place the ‘loose’ one armed bandits near any entrances.
Yet another standard rule is that loose slots are installed on the major aisles inside the casinos, again so that more fun seekers could see winning jackpots and be motivated to play. Importantly 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!
In recent times, casinos are constantly changing their philosophy about where to place the loose slot games.