This paper aims to explore the characteristics of self-regulated learning from information gained in post-questionnaire interviews, with special emphasis on the differences between low-proficiency learners and high-proficiency learners. Self-regulated learning is a cyclical process to metacognitively, motivationally, and behaviorally boost learning performance (Zimmerman & Schunk, 2001). Fukuda (2018a) quantitatively revealed the motivational and cognitive differences of self-regulated learning skills between the low- and high-proficiency groups, showing that self-regulated learning significantly influenced language learning achievement, which is consistent with most other studies. However, those have not addressed less-proficient learners enough to understand how they perceive self-regulated learning. Seven low-proficiency learners and ten high-proficiency learners participated and were selected based on a questionnaire regarding self-regulated language learning. The researcher adapted semi-structured interviews based on the factors in the Motivated Strategies for Learning Questionnaire (MSLQ). The results showed the obvious characteristics that the less-proficient learners possessed. Interviews consistently revealed that the less-proficient learners had a peculiar self-regulated learning attitude that was different from the more-proficient learners. Because the less-proficient learners strongly emphasized the outcome of the exams or performance compared to others, they tended to rarely feel successful in their English education experience, which seemed to cause them to give up learning English and make them reluctant to ask teachers for help. These tendencies demonstrated the importance of teacher encouragement of learner motivational satisfaction and the promotion of the use of various metacognitive strategies.