Books have been stated on this topic, and the bickering and disharmony about where the "hot" slot machines are positioned in a casino are still happening – more than sixty yrs after the slots were 1st installed in gambling houses.
The standard rule is that the superior slots were installed just inside the main doorway of the casino; so that persons passing by would be able to see jackpot winners … be aroused to come into the casino and play. Our resolution is that this is definitely no longer the case.
Practically all of the major casinos these days are giant complexes and it is not possible to see inside from the sidewalk, so there is no longer a reason to situate the ‘loose’ one armed bandits close-by any of the doors.
Another classic rule is that loose slots are located on the major aisles in the casinos, again so that more people could see winning jackpots and be encouraged 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 slot games 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!
In recent times, casinos are constantly changing their philosophy about where to place the loose slot machine games.