How do Roger's actions change during the story? Why do they change?
Roger is first introduced when he attempts to snatch Mrs. Jones' purse in an almost empty street. But soon, he realizes he has put himself in danger. His target, Mrs. Jones, proves to be too strong for him. He gets caught by her. He uses all of his strength to break away from her hold but fails to do so.
After some time, Roger finds the door of Mrs. Jones' house ajar. He feels a strong urge to run, but he isn’t sure. Before he can decide, Mrs. Jones resumes the conversation.
A little later, when Mrs. Jones goes “behind a screen” in another corner of the room to fetch a “gas plate and an icebox”, Roger could have easily run away. Even the purse is kept on day-bed close to him. But he doesn't do so. It’s because “he did not want to be mistrusted now.”
A thief a few moments ago now wishes to be trusted and believed. More than running away with money or valuables, he desires to bask in the warmth of human affection. This is certainly some transformation.
How does this happen? The warmth of motherly love effects this change in him. A stranger, whom Roger had tried to rob, offers him food and drink. She is the first person under the sun who bothers about his dirty face and disheveled look. She offers him her towel and comb to make himself presentable. Later, she shares personal information with him, much like a mother or a very close friend or relative would do.
Roger has been a thief. The society has always looked down upon him. However, the tenderness of human love and trust moves him so much that he ends up being changed into a sensitive young man from a petty thief.