Design is a rather broad and vague term. When someone says "I'm a designer," it is not immediately clear what they actually do day to day. There are a number of different responsibilities encompassed by the umbrella term designer. UX designers are primarily concerned with how the product feels. A given design problem has no single right answer. UX designers explore many different approaches to solving a specific user problem. The broad responsibility of a UX designer is to ensure that the product logically flows from one step to the next. One way that a UX designer might do this is by conducting in-person user tests to observe one's behavior.