About 1/2 are returning to college: (However, the fact that 1/2 of recipients of a very prestigious award (and the associated money/opportunity)).
No one is forcing them: (decided)
Presumably they made the choice by deciding it would benefit them to do so (because it keeps their options open, maybe, and maybe other reasons as well): (it was in their best interest to return to university).
I don't see the flaw is reasoning here. Help?