I think Liam is too inflexible for Steffy. She can never live up to his expectations and maintain her own sense of self. She needs to be able to make decisions without having to constantly defend them to the man who is supposed to love and support her.
Why can't he love and support her unconditionally? Why does he tell her that her father, uncle or brother are better choices for CEO? Who is he to tell her that her dreams and ambitions must be vetted by him before she can reach for them? Who needs a downer like that for a partner?