The problem is she pretended to be an amateur. She did everything she could to create the "Susan Boyle" effect, from the way she announced she was singing "Tomorrow" (making it sound like she was some kind of modern day "Baby Jane"; see the Altman movie if you don't get the - obviously relevant - reference); everything she did was a calculated manipulation of judges and audience in this direction, like pretending to be unaccustomed to performing onstage, the fake awkwardness. The deception is very clear.
