I'm guessing that our hypothetical student must or might take a college-level Biology course as part of their undergrad degree, and that exposure might cause them to change their mind about their chosen field.
I also don't know how easy it is to get into the same college at 20 that one would have gotten into at 18. If at 18 they got accepted to a school that cost 100K/year (as the parent comment suggests) then they may find that school closed to them 2 years later.
I also don't know how easy it is to get into the same college at 20 that one would have gotten into at 18. If at 18 they got accepted to a school that cost 100K/year (as the parent comment suggests) then they may find that school closed to them 2 years later.