Books have been stated on this issue, and the controversy and feuds about where the "hot" slot machines are installed in a casino are still on-going – over sixty yrs after slot games were first added to the gaming floor in gambling houses.
The traditional rule is that the very best slot machines were installed just inside the main entryway of the casino; so that fun seekers walking by would see jackpot winners … be stirred to come unto the gaming floor … play. Our sneaking suspicion is that this is not so anymore.
The majority of the big name casinos these days are magnificent complexes and you no longer can see inside from the sidewalk, so there’s no longer a reason to situate the ‘loose’ slots close-by any entrances or exits.
An additional classic rule is that loose slot machines are put on the major aisles in the casinos, again so that more people could see winning jackpots and be motivated 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 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 slot games.