Because she knew that she was under constant observation, she didn't try to sneak down into Level Eleven again. Dolores Umbridge was a sneaky element that she should've expected. Their mutual disdain and hatred never wavered over the years. The file clerk wasn't likely to forget her attack by the centaurs in Hermione's fifth year and the role the younger witch played in it. Hermione would never forget all of the disgusting, devious antics of the disgraced official over the years that the war was still in full effect. She knew that if given half a chance, Umbridge would bring her down. For all she was aware, she might even have an alliance with Rabastan. The wizard hadn't been silent about his desire for Hermione to disappear again. Even if he hadn't said it to her face, she had other avenues to discover what he'd been saying behind her back.