Since the late 1970s numerous studies have explored students' approaches to learning (referred to as the "SAL" tradition). These studies have provided valuable evidence of students' study strategies and intentions at the university. Since extensive research already exists on students' approaches to learning, there is a need to move forward and analyse student learning from new perspectives. In the present in-depth qualitative study, we analyse interviews of 34 students who scored extremely highly on the deep approach scale in a pre-test in our previous quantitative study (Lindblom-Ylänne, Parpala & Postareff, 2013) and thus are likely to have a strong commitment to understand, and a "disposition to understand for oneself" which is a recently introduced, yet unexplored phenomenon (see Entwistle & McCune, 2009; McCune & Entwistle, 2011). We identified several individual and contextual elements which provided explanations for the students' high scores on the deep approach, as well as for the increase, decrease or stability in their deep approach during one course. The results showed that most students showed a strong commitment to understand, but those whose deep approach sharply decreased during the course showed less commitment and their descriptions revealed problems with, for example, study skills, time management and regulation of learning. However, contextual elements such as the students' experiences of the course teaching and their interest in the course content did not clearly provide explanations for the changes in the deep approach. Elements of a "disposition to understand for oneself" clearly emerged among students whose deep approach did not decrease, or decreased only slightly.