If you think about watching a video online, it may seem pretty easy. A player, a play/pause button and some content. Done. But what about if the video is being played on a mobile phone? Or on a big screen? What if it's being viewed in Nairobi? Or Shanghai? Now let's say it's being viewed by someone who wants to share her thoughts on the video and by someone who wants to do nothing more than watch more videos. Before you know it, watching a video becomes more complicated than you realize.
Enter user research. While far from providing all the answers, it can help illuminate how the site is actually used -- as opposed to guessing how it might be used or assuming the user is just like the people designing the site.