It is King Lear himself who undergoes the greatest change during the play. In the beginning he shows himself, in spite of his age, to be selfish, self-centered, self-willed, and out of touch with reality. He gives his kingdom away to two daughters whose declarations of love for him are obviously only motivated by greed, while at the same time he disowns the daughter who fails to flatter him sufficiently. At the end of Act 1, Scene 1, Goneril and Regan express their true opinions of their father to each other. Regan says, "...yet he hath ever but slenderly known himself." Goneril says, "The best and soundest of his time hath been but rash..."
When Lear goes to live with Goneril, he and his one hundred knights create chaos with their unhibited behavior. Lear just wants to enjoy himself in his retirement, but he doesn't realize or care that he is making a bad impression. In Act 1, Scene 3, Goneril says of her father, "Old fools are babes again, and must be used / With checks as flatteries, when they are seen abused."
When Lear finds himself out in the cold, he begins to realize that he has been a fool all his life. First he has to accept his own insignificance and his mortality. Then he starts to think about other people--his own subjects--many of whom have been suffering all their lives as he is suffering now.
In the end Lear has learned humility and the value of true love. He has learned to despise pride and ostentation. He tells his daughter Cordelia, "We will laugh at gilded butterflies," meaning at overdressed courtiers with their ridiculous speech and mannerisms. The viewer cannot help feeling that Lear has become a much better person than he was at the beginning and that all his sufferings have done him good.