I'm not great at learning things myself and benefit greatly from having an instructor, but personally I feel like I need to completely understand something to say that I've actually "learned" it. So for me, getting a CS education was huge for me in terms of learning how and why things work the way they do, which really helped my confidence in feeling that I really know what I'm doing.

I've also learned about things such as linked structures which I probably wouldn't have bothered to look into if I taught myself, and are actually some crucial things that companies look for when they hire.

Another thing I've noticed personally is just a faster progression. I have a friend who taught himself how to make iOS apps, and it took him 3 years to get to the point that I did after taking one online course on iTunes U for it. Having a structured course really makes a huge impact by providing a logical progression and teaching you all the little things that take a long time to learn on your own.