Books have been set forth on this matter, and the contention and discourse about where the "hot" slot machines are positioned in a casino are still happening – over 60 yrs after slot games were 1st installed in gambling houses.
The standard rule is that the more favourable slot games were located just inside the entry of the casino; so that potential gamblers going by would be able to see actual jackpot winners … be titillated to come unto the gaming floor … play. Our speculation is that this is no longer the case.
Nearly all of the big name casinos nowadays are herculean complexes … you can no longer see inside from the sidewalk, so there is no longer a reason to position the ‘loose’ slots close-by any doors.
Another traditional rule is that loose slot games are positioned 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 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 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 one armed bandits.