Books have been set forth on this issue, and the conflict and ruckus about where the "hot" slot games are placed in a casino are still on-going – over 60 years after one armed bandits were 1st placed in gambling dens.
The traditional rule is that the more favourable slot games were located just inside the door of the casino; so that potential gamblers going by would be able to see jackpot winners … be smitten to come unto the gaming floor and play. Our reckoning is that this is definitely no longer true.
The majority of the major casinos these days are monstrous complexes and now you can’t see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slot machines close to any doorways.
Yet another standard rule is that loose slots are placed on the major aisles inside the casinos, again so that more potential players could see winning jackpots and be encouraged to play. Notably though, 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 one armed bandits.