Why is Derry initially reluctant to talk to Mr. Lamb?

Derry is initially reluctant to talk to Mr. Lamb because he is self-conscious about his disfigured face and fears that Mr. Lamb might judge him. He is also wary of the older man’s presence and the fact that he lives alone in a large, seemingly intimidating house. Derry’s past experiences with people staring at him or avoiding him because of his appearance make him hesitant to open up. However, as the conversation progresses, he begins to feel more comfortable due to Mr. Lamb’s understanding and non-judgmental attitude.

This question related to Chapter 5 English Vistas Class 12th NCERT.
From the Chapter 5, On the Face of It.
Give answer according to your understanding.