Reasons for studying Japanese

Post-Soviet states in Central Asia have little economic or human exchange with Japan and are therefore defined as ‘isolated Japanese language learning environments.’ Numerous conversations with university students in these countries have led me to a puzzling discovery. While first-year students are usually ardent Japanese learners, many lose interest as they approach graduation.
This experience prompted me to explore the motivation and goals of students choosing to major in Japanese.
Why study Japanese? Naturally, every learner is driven by multiple reasons. Additionally, their desire to learn may wane or intensify along the line. I am trying to deduce how an educator can support students and keep them motivated.