The problem with releasing useless and unfinished projects is that when people are taking your github profile as your resume, they're going to be seeing a bunch of useless, half-finished projects. It doesn't make a very good first impression.
For this reason, I'm increasingly moving my code off Github and onto Bitbucket. Despite having a worse UI, Bitbucket at least allows me to make private repositories for free, which means that I can make repos public if and only if I think it's ready for an interviewer to look at it.
Anecdotally, as someone who occasionally I never "penalize" people for having lots of unfinished projects. If they try interesting things a lot, that's a plus.
For this reason, I'm increasingly moving my code off Github and onto Bitbucket. Despite having a worse UI, Bitbucket at least allows me to make private repositories for free, which means that I can make repos public if and only if I think it's ready for an interviewer to look at it.