Too Long; Didn't Read
User research is a form of research conducted with interviews, but there are limitations. Product managers and designers are limited in their ability to speak with an actual user. Take a course on your users' domain of expertise and try to step into your user's shoes yourself. The key here is not to look at the implementation of a product, but to try and understand what customer need were trying to address. It's critical to remember that your users might not have the exact exact problems that you can discuss with your customers in the next interview.