Books have been set forth on this subject, and the contention and feuds about where the "hot" one armed bandits are installed in the casino are still intense – over 60 yrs after the slots were first added to the gaming floor in gambling dens.
The classic rule is that the more favourable slot machine games were put just inside the main entry of the casino; so that folks walking by would be able to see jackpot winners … be smitten to come unto the gaming floor … play. Our view is that this is no longer the case.
Most of the mega casinos nowadays are giant complexes and it’s no longer possible to see inside from the sidewalk, so there is no longer a reason to position the ‘loose’ slot machines near to any of the doors.
Another standard rule is that loose slot machines are placed on the major aisles in the casinos, again so that more folks could see winning jackpots and be roused to play. Nonetheless, 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 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 slots.