Looking into the article, they don't start from zero:

It helps that Hackbright students usually aren’t starting from scratch, but have instead developed their initial skills using Codecademy or by attending development workshops. After all, Phillips said, Hackbright is for people who are serious about programming as a profession, and you can’t decide that you’re serious until you’ve tried it out.

So as I see it's for somebody who knows some basic programming but wants to get some skills that would get her hired.