The concept of learner engagement, widely researched in educational psychology, has recently gained attention of language acquisition researchers (cf. Mercer, S. and Z. Dörnyei. 2020. "Engaging Students in Contemporary Classrooms." Cambridge: Cambridge University Press; Mercer, S. 2019. Language learner engagement: setting the scene. In "International Handbook of English Language Teaching," ed. X. Gao, C. Davison and C. Leung. Cham: Springer; Philp, J. and S. Duchesne. 2016. Exploring engagement in tasks in the language classroom. "Annual Review of Applied Linguistics" 36: 50-72. DOI:10.1017/S0267190515000094). The study of the construct in connection with language learning appears a promising line of enquiry since it might help teachers understand in greater depth how to promote engagement and prevent disaffection. The present study looks into learner engagement and the lack of it from the perspective of a language teacher. Semi-structured interviews were conducted with eight language teachers to establish descriptors of both states, possible causes, as well as steps teachers take to counteract disaffection and enhance involvement and agency. As the results suggest, teachers concentrate on the behavioural dimension and have little access to learners' emotions and less concern for other components of the construct. Some teachers in the context studied (higher education in Poland) tended to believe that changing learners' attitudes remains beyond their control as they are related to deeply ingrained beliefs and fixed general dispositions, whose origins can be traced back to early childhood, negative school experiences or lack of parental encouragement.