Books have been said on this subject, and the controversy and feuds about where the "hot" slot games are located in a casino are still passionate – over 60 yrs after slot machines were 1st placed in the casinos.
The traditional rule is that the better slot machine games were positioned just inside the main door of the casino; so that fun seekers going by would see jackpot winners and be stirred to come unto the gambling floor … play. Our sneaking suspicion is that this is definitely no longer so.
Most of the large casinos these days are grand complexes and you no longer can see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slot machines in close proximity to any of the doors.
An additional classic rule is that loose slot games are put on the major aisles inside the casinos, again so that more fun seekers could see winning jackpots and be energized to play. Importantly though, we find that this also is not 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 one armed bandits 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!
Nowadays, casinos are constantly changing their philosophy about where to place the loose slots.