Books have been said on this matter, and the disquiet and squabbling about where the "hot" slot games are placed in the casino are still happening – over 60 yrs after slots were 1st placed in the casinos.
The standard rule is that the better slot games were positioned just inside the main foyer of the casino; so that folks passing by would be able to see real jackpot winners … be enticed to come inside … play. Our leaning is that this is no longer the case.
Practically all of the large casinos these days are gigantic complexes and you can no longer see inside from the sidewalk, so there’s no longer a reason to have the ‘loose’ one armed bandits near any entrances or exits.
Another traditional rule is that loose slot games are put on the major aisles in the casinos, again so that more people could see winning jackpots and be inspired to play. However, 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 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 machines.