At last count I had around 87 repositories on Github, and to say more than a tenth of them resemble something complete would be a flat out lie.
However, I think this is where the pinned repositories feature comes in handy that Github has. Using this, you can mark about 6 of your projects that you want to be displayed on your profile.
Generally I think people will check out the projects that are pinned over digging through your Github graveyard. Most developers have abandoned projects or things that are just experiments. I actually think having these is a greater asset over not having them as it shows you are willing to try new things, or move on from a project that wasn't going anywhere.
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