Markus Zusak has this to say about his book, The Book Thief.
The Book Thief was supposed to be a small book - only a hundred pages or so. When I was growing up, I heard stories at home about Munich and Vienna in war-time, when my parents were children. Two stories my mother told me affected me a lot. The first was about Munich being bombed, and how the sky was on fire, how everything was red. The second was about something else she saw...
One day, there was a terrible noise coming from the main street of town, and when she ran to see it, she saw that Jewish people were being marched to Dachau, the concentration camp. At the back of the line, there was an old man, totally emaciated, who couldn't keep up. When a teenage boy saw this, he ran inside and brought the man a piece of bread. The man fell to his knees and kissed the boy's ankles and thanked him...Soon, a soldier noticed and walked over. He tore the bread from the man's hands and whipped him for taking it. Then he chased the boy and whipped him for giving him the bread in the first place. In one moment, there was great kindness and great cruelty, and I saw it as the perfect story of how humans are.
When I remembered those stories, I wanted to build them into a small book, like I said. The result was The Book Thief, and it came to mean much more to me than I could have imagined. No matter what anyone ever says about that book, whether good or bad, I know it was the best I could do, and I don't think a writer can ask for more of himself than that.