7. The "Acting"
The advantage of using no-name, unrecognizable actors is that it adds to the sense of realism that found-footage movies try so hard to create. Itd be pretty hard to pass off
Paranormal Activity as a real home movie if we saw Nicolas Cage or Ethan Hawke wandering around inside the frame. Using amateur actors is essential in making the illusion believable. Beyond that, though, they dont really bring much more to the table. The reason that some of these unknown actors are unknown is because they dont have the chops to carry the big scenes when they matter. Maybe they can lend an authentic scream or two, but scenes that require real pathos, they come up empty-handed, or even distractingly bad. Genre movies, and horror movies especially, arent usually known for great acting anyway. But when so much work goes into to creating the illusion of reality, its a real disappointment when the performers break the illusion.