You're saying the film was made purposefully bad, but you're missing that it was made to represent the raw video footage from a crew of young amateurs.
In this sense, the achievement is to emulate how this rough film might appear and sound.
It succeeds magnificently. Following the usual cinematic codes to produce endless clones of bogeymen and vampire movies is textbook and uninteresting - getting the right blend of cinema verite but managing to sustain audience interest though subtle visual and aural manipulation is very difficult indeed.
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