* Her "Too Easily Impressed": The Duke is angered by the Duchess's tendency to be "too easily impressed" by things like "a heart—a cherry, my last Duchess said." This suggests she showed a general openness and appreciation for the world, which the Duke sees as a weakness. He prefers a more controlled and subservient demeanor.
* Her Lack of Exclusivity: The Duke complains about her "smile" being "given to all," highlighting his possessive nature. He wants her attention and affection to be solely for him, and he resents the idea that she might find joy in interactions with others.
* Her "Too Much" Joy and Gratitude: The Duke expresses displeasure at the Duchess's "too much" gratitude for "small things" and her general "joy." This suggests that he found her spontaneous expressions of happiness to be embarrassing or even disrespectful.
* Her Unwavering "Gaze": The Duke mentions that her gaze "never turned" from the objects she admired, hinting that he may have felt ignored or excluded by her attentiveness to things other than himself.
* Her "Fault" in the Final Scene: The Duke never explicitly states how the Duchess died, but the chilling line, "I gave commands; / Then all smiles stopped together," strongly suggests that he had her killed. This reveals the ultimate level of his possessiveness and control.
In conclusion, the Duchess's "displeasure" stems from her independent spirit, her ability to find joy in the world outside of the Duke's control, and her inability to fully submit to his possessive demands. The poem exposes the Duke as a jealous, controlling, and potentially murderous figure who ultimately saw the Duchess as an object to be owned rather than a person to be loved.