A lot of people aren't driven enough by themselves. So although they -could- look things up and start working on projects, they -don't-.

Another thing is the teachers/mentors. I'm not sure about Lamba School's quality but in general having a teacher or mentor who can guide you is very beneficial. The thing with programming is that there's so much you have to learn at first.

I am also completely self taught. I learned Ruby to apply into one academy but got rejected. But I continued to work through their recommended materials anyway and now I work remotely fulltime as a software developer.