Books have been set forth on this issue, and the contention and feuds about where the "hot" slot games are positioned in the casino are still on-going – 60 years after the slots were 1st placed in casinos.
The quintessential rule is that the more favourable slot machines were put just inside the main entryway of the casino; so that potential players going by would be able to see actual jackpot winners and be smitten to come unto the gaming floor and play. Our standpoint is that this is definitely no longer the case.
Almost all of the mega casinos today are jumbo complexes and you no longer can see inside from the sidewalk, so there’s no longer a reason to have the ‘loose’ slot machines near to any doorways.
An additional standard rule is that loose slots are located on the major aisles in the casinos, again so that more people could see winning jackpots and be energized to play. Notably however, 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 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!
In recent times, casinos are constantly changing their philosophy about where to place the loose slots.