Most writers, myself included, initially resist making changes. It's a knee-jerk reaction: "No! You're just not getting it. It's perfect the way it is."
It's a perfectly natural response, but then you have to get over it.
Whenever I send an editorial letter to an author, I always tell them not
to respond right away. Take a few days to mull my suggestions over, sleep on them, and then
get back to me.