Learner engagement has been the focus of a growing amount of research in recent years both in general educational psychology and the field of second language acquisition (SLA). However, while recent contributions on learner engagement in language classrooms have provided valuable insights, the field is still only at the early stages of understanding the complexity of the concept and creating a strong empirical evidence base. This study is intended to contribute to our current understanding by investigating both learners' and teachers' perceptions on what might prevent motivated second language (L2) learners from engaging with language learning in and out of classrooms. A total of 39 learners and teachers were interviewed in two countries, England and Finland, and the results indicate a variety of potential reasons for motivated learners' disengagement, including disengaging classroom tasks and activities, the challenge of language learning, as well as competing priorities in learners' lives. These findings point to potential practical ways of ensuring that learners' motivation translates into engagement.