In many films based on Steven King novels, there is an explanation of why stuff exists or is happening. But in 1408 (2007) I've never got an explanation, why the room is cursed exactly, and what makes it evil.
I do know that the room mainly plays with your mind, so you think that all of this is happening, but in reality it's not (except for some things, like Mike's daughter). I still have no idea, what being plays with your mind.
The prologue of King's original story states (not verbatim, this was taken from the Wiki page):
After his ordeal, Enslin gives up writing altogether. He has acquired various physical and psychological problems stemming from his brief stay in the room. He notes to himself (as Olin expressed earlier) that there are no ghosts in 1408, because ghosts were once merely humans, while the entity he encountered was horrifically inhuman. In the end, Enslin sleeps with his lights on, has removed all his house's phones, and always draws the curtains before dark; he cannot stand the shade of yellow-orange at sunset that reminds him of the light inside Room 1408.
The director shot 3 separate endings, but ultimately none of them really reflected King's ending.
He is dead and in purgatory that is why 1408 acts the way it does. What Mike did while alive put him in 1408. https://en.wikipedia.org/wiki/Purgatory
