Volumes have been stated on this matter, and the bickering and arguments about where the "hot" video slots are located in the casino are still on-going – sixty yrs after slots were first installed in gambling dens.
The standard rule is that the very best one armed bandits were put just inside the main doorway of the casino; so that persons passing by would see jackpot winners and be convinced to come into the casino and play. Our assessment is that this is definitely no longer the case.
Practically all of the major casinos today are magnificent complexes … it is not possible to see inside from the sidewalk, so there is no longer a reason to put the ‘loose’ one armed bandits near to any doors.
An additional standard rule is that loose slot machines are installed on the major aisles inside the casinos, again so that more persons could see winning jackpots and be encouraged 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 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 perspective about where to place the loose slots.