Books have been written on this subject, and the bickering and disagreement about where the "hot" slot machine games are installed in a casino are still on-going – more than sixty years after one armed bandits were 1st placed in casinos.
The classic rule is that the best slots were positioned just inside the main doorway of the casino; so that fun seekers passing by would see jackpot winners … be captivated to come inside … play. Our reasoning is that this is no longer true.
The great majority of the large casinos presently are grand complexes and you can no longer see inside from the sidewalk, so there’s no longer a reason to put the ‘loose’ slot games close-by any exits.
An additional traditional rule is that loose slots are put on the major aisles inside the casinos, again so that more folks could see winning jackpots and be encouraged to play. Interestingly 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 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 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!
Today, casinos are constantly changing their perspective about where to place the loose slot machine games.