Wow, this thread has been a learning experience for me. I came from a background where the understanding was that everyone would go to college, and a college degree takes four years to earn. So, I had a bunch of AP credits from high school, went to a good private college, and graduated with a BA in Political Science in four years. I double-majored in Chemistry, too, but my college lets undergrads choose only one bachelor's degree, no matter how many majors they can finish. I suppose there were at least some people who disappeared after the first year of college (transferred, or took time off?), but it seems like the overwhelming majority finished a bachelor's degree in four years. I also had a handful of friends who did it in three years.
Now, I'm a lawyer at a big law firm, and it seems that most everyone did their bachelor's in four years. However, one of my closest colleagues, who is extremely smart and has a knack for finding good practical answers, had a pretty circuitous route to get here. She told me her "big secret" (said with a smile) was that she did not graduate high school, but instead got her GED. After a while of working, she took night classes in state school to get her bachelor's. A few years later, she continued with night classes at a state law school. Now she is here at "prestigious BigLaw" just the same as others who took a more traditional path, and she is excelling.