Books have been written on this subject, and the bickering and ruckus about where the "hot" slot machines are located in a casino are still rampant – over sixty yrs after the slot machines were first placed in casinos.
The classic rule is that the more favourable slot machine games were placed just inside the entry of the casino; so that casino fanatics passing by would see actual jackpot winners and be smitten to come inside and play. Our position is that this is not so anymore.
The great majority of the big name casinos these days are super-colossal complexes and you can no longer see inside from the sidewalk, so there is no longer a reason to have the ‘loose’ slot games close-by any exits.
An additional classic rule is that loose slots are put on the major aisles in the casinos, again so that more people could see winning jackpots and be roused to play. Nonetheless, we find that this also isn’t 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 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!
These days, casinos are constantly changing their philosophy about where to place the loose slot machines.