Răspuns:
This statement can be taken to mean that people can change a lot with the passage of so much time; and that people's bad side will show more if they persist in their unlawful behavior long enough. Clearly this is said to increase the realization that after "twenty years" it's less probable the things are the same as you would expect them. It can be seen as an element of sadness which is meant to enhance the story's purpose.
