Empathy.
Empathy is key in user research because it involves understanding the users' needs, goals, and experiences in order to design products that meet their needs and improve their overall experience. User researchers need to have a deep understanding of their users, which requires empathy and the ability to put themselves in the users' shoes. This understanding is then used to inform the design of the product, and to make improvements based on user feedback. While surveys, questionnaires, reporting, and fundamentals are important components of user research, empathy is the foundation that underpins all of these activities.