[PretzelFisch]

You never really know when the market would be saturated with degree x since it takes 4 years to earn. On the other end banks may decline a degree that if taken now will start to be high demand when the candidate graduates.

[bluGill]

If you have a electrical engineering degree in generators right before someone discovers a cheap over unity solar panel (coming up with a way to violate the laws of physics is left as an exercise to the reader) thus making all generator specialists valueless - most of your EE course work still applies so you just need pivot a little. Maybe you need an additional year of school to get in demand skills, but the odds that you can't find something that it is a low risk to get you into is low.

If you have a degree in music - we already know that field is saturated. If you studied only music you have a few years left to get a course of study that is useful.