Why are people so against my enlistment?

I've already enlisted with the Army, as a 92W, for three years. I'm ecstatic and can't wait until my ship out, but...my parents don't think its wise, because they rather I go to college, and then try to get into OCS, and along with friends, who are scared for me, and think I'm acting out a little bit too early and irrationally. Hell, even one of my teacher say he bless our troops, but wouldn't recommend joining the military. This is what I want. I think I'm making the wisest choice I'd ever made. Sorry for the rant. As for question, is it hard to go from enlisted prior to OCS? I know there are some ways to go about, but I want to know how many actually get in.