Volumes have been stated on this topic, and the controversy and discourse about where the "hot" slots are located in a casino are still happening – 60 yrs after the slots were first installed in casinos.
The quintessential rule is that the most favorable slot games were installed just inside the main doorway of the casino; so that individuals walking by would see jackpot winners and be mesmerized enough to come unto the gaming floor and play. Our feeling is that this is no longer the case.
Nearly all of the major casinos these days are giant complexes and now you can’t see inside from the sidewalk, so there’s no longer a reason to place the ‘loose’ slot machines close-by any entrances.
An additional classic rule is that loose slot games are installed on the major aisles in the casinos, again so that more potential players could see winning jackpots and be energized to play. Notably 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 machine 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!
These days, casinos are constantly changing their perspective about where to place the loose slot machine games.