Volumes have been said on this topic, and the conflict and discussion about where the "hot" slots are installed in a casino are still taking place – over sixty years after one armed bandits were 1st placed in casinos.
The quintessential rule is that the best slot machines were installed just inside the main entry of the casino; so that persons going by would see jackpot winners and be intrigued enough to come inside … play. Our thought is that this is definitely no longer the case.
The great majority of the large casinos nowadays are herculean complexes and you no longer can see inside from the sidewalk, so there is no longer a reason to situate the ‘loose’ one armed bandits close to any of the doors.
An additional traditional rule is that loose slots are positioned on the major aisles inside the casinos, again so that more potential gamblers could see winning jackpots and be galvanized to play. Notably 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 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 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 slots.