I agree. For the longest time my github had little in it except school projects. I finally decided to use it for personal stuff, or more like got used to the idea that my code would be public. I put up a few projects and even then, I didn't do anything to even try to show them off. This is because of the fear of being judged and because in my mind I'm not nearly as good as the people here or the people who post on /r/programming. Eventually, I posted my projects to a few sites and while the feedback wasn't "oh this is great", it was feedback nonetheless and I was able to take it and improve my project and myself.

I guess where I'm going with this is that for those who are beginning or come from a non-CS background, seeing all this polished code, even in initial commits, being posted to sites like HN or reddit is very intimidating and could be a drawback from people sharing their code.