The worst movie I've seen is the Poltergeist remake. If you've seen it you know why, but basically it boils down to a combination of toning it way the hell down and breaking the main rules of horror.
They showed the "mysterious spooky ghost world" at the end and it was basically just the house but dark and fuzzy. They also had scenes that were obviously meant as watered down replacements for scenes in the original movie. They replaced the scene where a guy peels his own face off with a scene where a drill goes through a wall
I've watched every single Steven Seagal film so I feel I'm a pretty good authority here. The worst film of all time is Super Mario Bros (1993)
I can talk about Tommy Wiseau and Neil Breen all day, but these are lunatics funding their own crazy films. Mario bros is something else.
It had the actors. It had the funding. It had the IP. They missed the mark so badly they ruined video game-based films for over a decade. . I seriously felt depressed for hours after watching this film.
@GiveOver Straight up love that film. It's indeed 100% hot fucking garbage and has almost zero redeeming value..but goddamn it's just too fucking stupid for me not to laugh at and end up loving.