I love what Dan said about asking what users do 3 mins before and after using your product.

I think the best product people know how to extrapolate better than others. Its one thing to gather feedback and observe users, but its much more challenging deciding what to do with that information. Simply asking users what they want wont always give you the best outcome. Someone once said, although Henry Ford is often credited, "if i had asked, people would have wanted faster horses". Theres some truth there. Its about the ability to observe customers and extrapolate the features.