The knight's punishment for rape is a quest in which he must discover what women most desire. This plot element is an occasion for the tale to expound upon all of the various things women desire and, in some cases, what these desires reveal about their nature.
Although "The Wife of Bath's Tale" begins with the sexual assault of a woman, the rest of it imagines a world in which women are sovereign and in which they mete out judgments, administer justice, and have power over men's bodies. This world is the one that women want, at least according to the loathly lady's assertion that what women most desire is sovereignty over their husbands and lovers. Yet curiously, at the end of the tale, the loathly-lady-turned-beautiful-wife yields power back to her husband despite his willingness to grant it to her, raising questions about what it is women really desire. This ending is in keeping with the wide variety of things people tell the knight women most desire, for, at the end of the tale, women turn out to be just as big of a question mark as they were in at its beginning.
"The Wife of Bath's Tale" portrays a world in which the desires of women take precedence over all other considerations.
"The Wife of Bath's Tale" suggests that contrary to its own assertion that women most desire sovereignty over their husbands and lovers, what women actually desire is their husbands' willingness to yield sovereignty.