This, at least, is Death's final assessment of humanity in Markus Zusack's The Book Thief. The Grim Reaper, having witnessed both the worst examples of hateful human behavior (in Hitler and Nazi Germany) and also the best that humanity has to offer (in the Hubermanns' sacrifices for Max), ends his story with the words, "I am haunted by humans."
This haunting (which is a wonderful reversal -- Death afraid of humans instead of the other way around) seems to stem from Death's recognizing the inconsistent and indefinable nature of humanity.
How can it be, Death implies in his tale, that a people so capable of nobility and kindness and sacrifice can also be so capable of absolute hatred and evil?
All of this gives special meaning to one of Death's earlier statements:
And yet, Death also knows that humans are so definitely capable of kindness.
For example, when Death comes to collect the soul of an Allied pilot whose plane has crashed, he witnesses this:
"[Rudy] reached into his toolbox again and searched through some picture frames to pull out a small, stuffed yellow toy."
"Carefully, he climbed to the dying man."
"He placed the smiling teddy bear cautiously onto the pilot's shoulder. The tip of its ear touched his throat."
"The dying man breathed it in. He spoke. In English, he said, 'Thank you.'"
But that's only half the brilliance of The Book Thief. The rest is this:
And I am.