Why is Lear angry at Goneril?

Lear is angry at Goneril because she refuses to tell him how much she loves him, and compares her love to that of Regan, who speaks the most extravagant language of affection for her father. Lear sees this as a lack of respect and a betrayal of his love for her. This anger deepens when Goneril and Regan refuse to allow him to keep his knights with him and begins to turn against him, which leads to his eventual madness and downfall.