Alice was walking blind that day, her arms protectively out in front of her. She was just trying to make it to the Charms classroom, but was utterly lost. She thought she was on the third floor, no wait. Last time she went up stairs, it was down, which meant that she was on the ground floor or maybe the second floor.

Either way, Alice was lost, and walking dangerously close towards a staircase. Not that she knew that. For as much as she knew, she was on the ground floor, near the great hall. It's very difficult to keep track of where you are in the building, let alone when you can't even see.

One wrong foot placement, and Alice would have a very bumpy, and for that matter uncomfortable, ride down to the first floor.