What does the open door represent?

In Langston Hughes's "Thank You, M'am," Roger gets more than he bargains for when he attempts to steal the purse of Mrs. Luella Bates Washington Jones. He finds himself being lectured, reprimanded, and dragged to her home. Once there, Mrs. Jones instructs him to wash his face. The reader learns that Roger "looked at the door—looked at the woman—looked at the door—and went to the sink."
The open door represents a choice for Roger. He has an opportunity to escape, or he can choose to remain and accept whatever comes next from Mrs. Jones. It is interesting to note that although she holds him in a "half-nelson about his neck" to get Roger inside, she leaves the door open. Perhaps she is intentionally providing him with this choice in an effort to show that when good behavior and positive choices are the expectation, he will live up to that expectation.