1. They'll understand why they actually need it and will be more likely to take it seriously.
2. They'll likely have a better vision of what they want to do and thus a lesser chance of wasting time/money switching majors.
3. They'll, hopefully, have some money saved up from working for seven years beforehand in addition to a better money mindset that'll allow them to graduate with significantly less debt.
That's all I can think of for now. I think 25 is too late, though. Perhaps a better case could be made for starting at 21. Well, it's not actually too late, but I think it'd be smarter to start at 21, unless you have some incredible business opportunity or something.
Edit: Actually, perhaps the best case could be made for simply starting college when you're ready and excited about it. In the years beforehand, you should be working on independent projects, self-reflection, having interesting experiences, and holding down a job.