Volumes have been written on this topic, and the disquiet and face-offs about where the "hot" one armed bandits are installed in the casino are still on-going – sixty yrs after the slots were first placed in gambling dens.
The standard rule is that the most favorable slot machines were installed just inside the main entry of the casino; so that individuals going by would be able to see actual jackpot winners and be tempted to come unto the gaming floor and play. Our viewpoint is that this is definitely no longer so.
Almost all of the mega casinos presently are jumbo complexes and it is not possible to see inside from the sidewalk, so there’s no longer a reason to place the ‘loose’ one armed bandits close to any entrances.
Another standard rule is that loose slot machine games are positioned on the major aisles inside the casinos, again so that more people could see winning jackpots and be roused to play. Interestingly though, 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 slot games 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!
These days, casinos are constantly changing their perspective about where to place the loose slot machine games.