Continuity mistake: When Charlie invites Hiro over to help celebrate her birthday, the invite is almost immediately after she says "hold that thought" and walks away from his booth. But in that scene in the previous episode, Charlie was already across the room with the other townspeople when she signaled Hiro to come over.
Continuity mistake: When Hiro gives Charlie the Japanese phrase book, Charlie flips the book over to look at the back cover, then flips it frontwards again. In the next shot, she's instantly looking at the back cover again. (00:16:20)
Chosen answer: Because he's an idiot. From the story point of view, they needed the vault to actually be physically open so that the release of the virus would be a credible threat. Unfortunately, this required that Peter conveniently forget that he could simply walk through The Wall and use his telekinesis to tear the door open instead. Peter's increasingly large arsenal of abilities, where he ended up having pretty much any ability required for any situation, led to a situation where it became necessary to either have Peter apparently forget that he had a given power, as with the vault door scene, or become naively trusting, as with his refusal to scan Adam's mind to confirm his good intent. This problem, which simply made Peter look increasingly dumb as the show progressed, may well have been a key factor in the decision to severely reduce his ability during season three.
Tailkinker ★