* After Enslin receives the ominous "Don't enter 1408" postcard, it's never brought up again, not even with Mr. Olin. What would he have had to say if Enslin had shown it to him?
** Probably something along the lines of "Good advice. You should listen to it." Assuming the room itself somehow arranged for the postcard to be sent, Mr. Olin probably wouldn't have raised that possibility, since it would've just raised Enslin's interest in the room.
* If Olin really wanted to keep anyone from ever using the room why didn't he just have the windows and door carefully covered up? Heck, if he really wanted to keep Enslin out why didn't he simply claim that the room was undergoing renovations? It's not as though the law states that the hotel has to provide that specific room on demand.
** Actually it does. This is made a big point of in both story and movie. (The logic remains for sealing it off. The renovations answer would quickly break down for someone as determined as Mike, though.)
*** In the story, Olin explains that the owners don't believe the room is evil and would fire him if he tried to seal off the room.
*** The story also explains that due to civil rights laws that prevent things like the managers putting minority clients into crappy rooms, anyone who demands a specific room at a hotel can get it, as long as it's not occupied. Normally, Olin doesn't let guests into 1408, but since Enslin insisted on that specific room...
** Possible FridgeBrilliance: What if they tried that, and ''it didn't work?'' The room can clearly warp reality within itself, so it's not unrealistic for it to have enough control in the general vicinity to prevent its supply of victims from being cut off entirely.
* Why bother to clean the room? That just puts the cleaning staff in danger for no reason.
** They're required by law to clean every room after a certain amount of time, whether it's been occupied or not. As noted above, the room has to be provided if demanded, and it can't legally be occupied if not cleaned. To his credit, at least Olin employed specific safety measures in having the room cleaned, and while declining to do so is the logical choice, it's not the practical one.
* How do we know if the ending is real? Is he really out of that room or is he still there, trapped forever? The ending could be all in his head.
** Remember, the room is malicious. Making him think he defeated it and is living a normal life again isn't really mean enough to go through all the trouble.
* Hold on. Taking the time-loop into account, Lily arrives at the beginning of the hour -- 45 minutes before Mike contacts her on video-chat.
** That's assuming it is a time-loop. It seems more that time is whatever the room wants it to be. It didn't literally send him back to the beginning any more than it sent him forward to a burned room. It just sort of... made a new hour.
* At one point Enslin climbed out onto the ledge to escape and find that all the other windows of the hotel are just -- gone. Dumb question time. What if he'd just jumped or even fallen? Would he have died when he hit? Or would he have landed back in 1408's bed so it could torment him some more?
** Near the end of the film Enslin asks the room why they don't just kill him, and it explains that it likes to offer its guests free will. I like to think that the room only derives real satisfaction from guests choosing to kill themselves - if they do it by accident it's a bit of a cheat.
* Why does everyone dismiss the hallucinogens theory? Chocolates, pumped through the ventilation ...etc. A sufficient amount of prepared bizarre incidents (chocolates, toilet paper,...) complemented with the victim's imagination would be plausible for the film. As for Olin hearing and seeing things at the end, that happened after he touched the recorder, which could've still been carrying hallucinogens from the room.