My T has often said that he wants to feel useful, so when I need and get and use his help, he feels "gratified" (they must learn that word in T school!).

I can also infer what he gets, from my own experiences in an unrelated field. I am a teacher and no matter how hard it has been to work with a kid, I feel really good when I see that child grow and develop and become more independent and confident. It makes me feel proud to know that I had a hand in steering them that way. I suppose T feels that way, too.