That is a difficult question. Here's what my situation was at university:

95% of my class came straight out of high school and had no trouble catching up with the (incredibly difficult!!) material. The other 5% (including myself) started university at age 25-27, a lot of us didn't finish high school (went through community college for 2 years) and thus didn't have the awesome comprehensive theoretical background everyone else had.

The statistic sheets of my university showed less than 1% chance of graduating for people like me.. and 70-80% chance for the buttered-up, lucky little high school kids. Well.. I fought really hard, I sought every resource and person possible and finally I made it, I graduated.
For those spoiled high school kids: 15% dropped out in freshman year, 20% dropped out in the second year and 10% dropped out in the final year. From the 500 applicants, about 90 graduated. That's not much eh, you see?
My professor told me: "The actual statistics are: you have on average 8.25% chance of graduating once you set foot in university".

Long story short: If you did really well in high school, your chances of dropping out of college are 10 to 20%.
Mature people are likely to stay and super-determined people like me have to move earth and sun to make it. The only dropout factor here is your maturity, really.. A lot of childish morons didn't have the strength, courage or passion to continue, press on and graduate (these people don't even know those concepts to begin with. They're pampered like babies).

I hope my advice helps!

[i]P.S.: sorry for my lack of vocabulary but I'm rather tired at the moment.[/i]

If people only knew what they are facing, I wish I had it to do over again, I would go to school year round like in a lot of advanced countries. Same thing with college, no summer break would just waste it anyway. By the time my friends graduate college, I will have had my degree, work experience, and started putting money in my retirement fund. Who would your hire, the student who just finished college and has nothing to show you but their grades. Or the student who has demonstrated success by getting more done in the same amount of time and already has a couple of years work experience in the field.

Could be true.
Some folk will drift toward college because they don't know what else to do !
Maybe they think by extending their education it buys them time before deciding what they really want to do !
You'd have to know the drop out rate before you could know for sure.

Straight out of high school a lot of kids flunk out because they just party the whole semester. I don't know anyone who did dropout, but I did after 6 years and not getting anywhere. I refuse to go back now.

What reason did they give? I could see it working both ways--a gap year might be good for some but not good for others.

Unless they provided some empirical data to back their claim, it sounds like they should drop out.