Peer-assisted learning (PAL) is a common teaching and learning method in medical education worldwide. In the setting of skills laboratories (skills labs), student tutors are often employed as an equivalent alternative to faculty teachers. However, to the best of our knowledge, there is a lack of qualitative studies which explore the reasons for the personal commitment of student tutors. The aim of our study was to examine how undergraduate students experienced and evaluated their roles as skills lab student tutors, what their motivation was, and whether social and cognitive congruence played a role in their teaching experiences. We conducted in-depth, semi-structured interviews with student tutors who were currently teaching in a skills lab. After the interviews had been transcribed verbatim, two independent investigators performed a qualitative content analysis according to Mayring. In total, we conducted nine interviews with student tutors. Our results revealed that all student tutors showed great enthusiasm and motivation for their jobs as peer teachers. One of the main motivating factors for student tutors to teach in a skills lab was the possibility to simultaneously share and improve their knowledge and expertise. In general, the participants of our study had high aspirations for their teaching. They found it particularly important to be empathetic with the student learners. At the same time, they thought they would personally benefit from their teaching activities and develop a certain expertise as student tutors. With the present study we are able to gain some insight into what motivates student tutors to teach in a skills lab and what kind of experiences they have. Our results provide an important input for the future training of highly qualified student tutors.