When your partner says he is not satisfied with sex- do you realize it is serious issue or just ignore it?

I want to hear from people whose partner stated he or she was not happy with sex life. Want goes in your brian? Did you realize yes it’s something wrong or you need to do more work on yourself or situation to fix it or just ignored thinking partner has high libido?

There are lot of post of people unhappy about sex life but why is it difficult to make the partner understand that something needs to be done?

I want to hear the other side of story from people whose partner stated they were not happy with sex life.