Finland has free college education. Mainly for that reason, the future profitability of a specific discipline doesn't appear to be a major factor in how young Finns choose their majors (as evidenced by the enduring huge popularity of objectively unprofitable disciplines such as media and design).
It seems to me that those that become teachers in Finland have chosen the career fairly early on. It's a vocational thing. Money doesn't influence the decision, but of course there is the financial baseline that teaching is a stable job that offers an extraordinarily long summer vacation (something like 11 weeks, fully paid).
