Now, Mrs. Sparsit was not a poetical woman; but she took an idea in the nature of an allegorical fancy, into her head. Much watching of Louisa, and much consequent observation of her impenetrable demeanour, which keenly whetted and sharpened Mrs. Sparsit's edge, must have given her as it were a lift, in the way of inspiration. She erected in her mind a mighty Staircase, with a dark pit of shame and ruin at the bottom; a down those stairs, from day to day and hour to hour, she saw Louisa coming.
Based on the passage, which point is Mrs. Sparsit most likely trying to make with the staircase allegory?