Why self-teaching rarely works for young kids?

I once had a student who had great potential. After a long summer vacation, his mom notified me that the son wanted to learn by himself. I knew he could read a chess book like a novel by himself. It was a rare quality for little kids. But self-teaching? I had some doubts. After a year, he is still trying hang on to 1000. I can't say he had not made progress. He in fact did great in most people's view. But with his ability, he should do much better, and should get on the Top 100 list now.

I myself was self-taught, but I had professional training in Chinese chess when I was young, two hours a day, everyday. I self-taught myself Go. I understand what is important for beginners, how to train, and how to think. I understand when I just need to persist, what I should not spend too much efforts on right now. I know which books to read, and which books to avoid. I know what software I should use. I know how to choose tournaments and sections. I know where is my potential, and how to reach there. I know how to refuel my confidence.

For a little kid, where can he get or feel these tips by himself? He is just not mature enough.