Books have been written on this topic, and the disquiet and discourse about where the "hot" slot machines are located in the casino are still taking place – over 60 yrs after slots were first placed in gambling houses.
The classic rule is that the more favourable one armed bandits were installed just inside the main foyer of the casino; so that everyone walking by would be able to see jackpot winners … be convinced to come inside … play. Our frame of mind is that this is definitely no longer so.
Nearly all of the big name casinos today are monstrous complexes and now you can’t see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slot machines close to any of the doors.
Yet another classic rule is that loose slot games are placed on the major aisles in the casinos, again so that more potential players could see winning jackpots and be galvanized to play. Importantly though, we find that this also isn’t 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!
These days, casinos are constantly changing their philosophy about where to place the loose one armed bandits.