Understanding the Question:
This refers to Susan Hill's story 'On the Face of It', about Derry, a disfigured boy, and old Mr. Lamb.
Final Answer:
Derry, who was deeply self-conscious about the acid-burn scars on his face and avoided people, was impressed by Mr. Lamb because, unlike others, Lamb never stared at or pitied his scarred face, and instead treated him as a normal, capable boy. Lamb's open-mindedness, his cheerful philosophy of embracing life despite his own disability (an artificial leg), and his encouragement that Derry should not hide from the world impressed and moved Derry deeply.