When we first meet him, Roger is a young, "willow-wild" boy who is intent on snatching a purse to buy himself a pair of blue suede shoes. It hasn't occurred to him to ask for the money (or if it has, he is too proud to consider it). He is unwashed and unfed. He has a home to go to, but no one there to care for him. This changes when he tries to take Mrs. Jones's purse and fails. Instead of turning him in to the police, she shakes him and takes him home with her. She gains his trust by giving him the chance to escape, but he goes to her sink and washes his face instead, as she's told him to do. By the time she's cooking dinner, he is going out of his way to prove he can be trusted. By the time he leaves, he thanks her for her hospitality and calls her "Ma'am." Thus, he changes from a disrespectful thief into a respectful, trustworthy member of society.