He isnt always hard

Karla • 33 years young. Matteo, March 2018 👶🏼💙

Hi! I have a question. My husband and I are intimate almost every day. Sometimes, his penis is not that hard. He is erection but it is a bit soft. Sometimes he can be in the middle of sex and his penis starts going soft and he looses his erection. What could be the cause of this? He says he is attracted to me, so I dont know what it could be. Thoughts?