What do people do for a living if they don't become elementary school teachers after graduating from a teachers' college?

I heard that entrance scores for teachers' colleges have dropped significantly.
The reason is supposedly that even after graduating, you can't pass the teacher certification exam.
They say the cause is the declining student population,
but if that's the case, shouldn't they just stop admitting students to teachers' colleges altogether?
It feels just like graduating from a military academy but not being commissioned as a second lieutenant.
No matter how much military training you undergo, it's useless in society.
If the state recruits people into teachers' colleges to make them teachers, the state should at least provide them with jobs. ㄷㄷ