Why my(22M) wife(24F) doesn’t enjoy intercourse?

Married for good amount of time and we do love each other decently but it is me who initiates sex everytime, and she never does. Sometimes she doesnt want to have sex just because she feels sleepy and just want to cuddle instead.

I don’t have big penis (4inch when erect at best) and this is something i cannot change, but i do foreplay and i make her wet everytime but she doesnt haves an orgasm atleast none which i know of.

What could be the reason?