Student attrition and falling tertiary education enrolments afflict languages education across the "inner circle" English speaking world. In the southern hemisphere, in New Zealand and Australia, Japanese has become one of the most successful languages of education. However, numbers of students are now declining. This paper examines why successful secondary school students of Japanese as a foreign language (FL) in New Zealand who have not chosen Japanese as a major, do not continue their study of Japanese at university or another tertiary educational institution. It utilises a grounded theory approach to explain an area of language learning and attrition which is not currently well understood: the transition stage between secondary school and tertiary education. Analysis of interview data of former secondary students of Japanese revealed two core categories that explain why successful secondary students drop Japanese when they leave high school: the participants' "concept of learning Japanese" and "the incompatibility of Japanese and the major". In this paper, we look at the first of these categories in depth in order to explore these mainly affective reasons for post secondary school students not continuing Japanese at tertiary level. It is hoped our paper will prove instructive for other jurisdictions which are witnessing a decline in their Japanese language students and language students more generally.