Just prior to the "Five Nights at Freddy's" movie premiering, Bloody Disgusting interviewed Robert Bennett, who's credited as the film's project supervisor and lead designer. Bennett works for Jim Henson's Creature Shop, the company responsible for iconic puppets in numerous films and TV shows, including "Sesame Street" and "The Dark Crystal: Age of Resistance."
Bennett corroborated Emma Tammi's account of the puppets sometimes moving on their own. However, he claimed to understand what caused this to happen, demystifying some of the on-set creepiness. "I know that there were several times where there would be a signal between one of the remote controls and a servo would glitch, and Emma would be like, 'Oh my God, that's so amazing. Can we do that again?' Well, we'll try," he said.
He went on to explain that the "Five Nights at Freddy's" animatronics were designed so that they could appear intentionally glitchy when necessary. Filmgoers, then, may not be able to tell the difference between moments when the puppets legitimately act on their own and instances when the puppeteers are in command of some of their creepier movements.