This study explores how direct supervisors can hinder or enhance how professionals learn from their errors. Extant research has often focused on psychological safety as the main condition for this kind of learning to take place. We expand prior research by exploring which behaviors of direct supervisors effectively facilitate learning from errors in concert with psychological safety. We conducted semi-structured interviews among 23 professionals to gain detailed insights into their thoughts, needs, and the difficulties they encounter. Through content analysis, we identified four critical supervisor behaviors that participants viewed as facilitating learning from errors next to fostering a psychologically safe work environment: (1) providing timely feedback, (2) guidance and elaborate feedback, (3) being accessible and personally involved, (4) organizing joint evaluations. Based on our findings, recommendations are formulated for supervisors that aim to facilitate professionals' learning from errors and their professional development.