By the end of Pride and Prejudice, Elizabeth Bennet is a much wiser character. Her initial hastiness in putting too much stock in her first impressions is eroded when she gets to know Mr. Darcy and why he acts the way he does. Though she thought him rude and cold, he is in truth socially awkward though undoubtedly proud to a fault. Her assumption that he is cruel towards Mr. Wickham is also challenged when she learns of Wickham's misdeeds and past mistreatment of the Darcys. By realizing that her own judgmental nature has led her to trust a rake like Wickham and to despise a noble person such as Darcy, Elizabeth becomes less rash in her perceptions of others, particularly Darcy, as she slowly falls in love with him.
At the end of the novel, Elizabeth also becomes Darcy's wife. This fulfillment of her desire to marry for love only comes about because she has grown so much as a character. The earlier Elizabeth, who judged Darcy harshly, would have missed out on a love match due to her prejudices. Her prejudices would have quite literally thwarted her goals. She might even have been taken in by Wickham before he could get to Lydia. Now that she has undergone a shift in her perceptions of the world, she and Darcy are able to happily marry.