Books have been said on this topic, and the controversy and discussion about where the "hot" slot games are placed in the casino are still raging – over 60 yrs after slots were first placed in gambling dens.
The quintessential rule is that the superior one armed bandits were positioned just inside the main entryway of the casino; so that everyone walking by would see jackpot winners and be keen enough to come inside and play. Our interpretation is that this is definitely no longer so.
The great majority of the mega casinos these days are massive complexes and it’s no longer possible to see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slot machines near any entrances.
Yet another standard rule is that loose one armed bandits are positioned on the major aisles inside the casinos, again so that more folks could see winning jackpots and be influenced to play. 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 slots 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!
Nowadays, casinos are constantly changing their perspective about where to place the loose one armed bandits.