sentences:  J. M. Robertson also agrees with Frost's argument that Sonnet 128 and the other Dark Lady sonnets do not fit with Shakespeare's other sonnets.Purdum continues his argument stating that maybe because Shakespeare was writing about the Dark Lady, that his poor quality sonnet was caused by his growing infatuation with the Dark Lady.Purdum, and other critics such as, Barbara A. Mackenzie believe that Shakespeare's immense infatuation with the Dark Lady lead to Shakespeare failing to correct his mistakes within Sonnet 128.