Volumes have been stated on this topic, and the conflict and ruckus about where the "hot" slots are placed in the casino are still taking place – sixty yrs after slot games were 1st placed in the casinos.
The classic rule is that the better slot games were placed just inside the entry of the casino; so that persons passing by would see actual jackpot winners and be smitten to come unto the gambling floor … play. Our finding is that this is no longer the case.
Nearly all of the major casinos these days are colossal 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 near any entrances or exits.
An additional standard rule is that loose slot machine games are located on the major aisles in the casinos, again so that more potential players could see winning jackpots and be galvanized to play. Importantly however, 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 slot machines 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!
These days, casinos are constantly changing their philosophy about where to place the loose slot games.