I've seen some people making blog posts that equate to something like: "Hey, play my crappy game!" And I personally think one should refrain from writing about their work like that, for two reasons:

• It's instinctively clear to the person reading that the game itself likely isn't completely crap, given that the creator is asking for it to be played. But it displays a lack of confidence in the project that will ultimately put people off from approaching it. You can acknowledge your project's weaknesses, but focus on the strengths! Entice people to play it, rather than offer an easy way out not to!
• Effort and time into the project was put into it. Even if you genuinely believe it turned out horrific and can't find any strengths to speak of, the project isn't worthless. Simply ask for feedback, without putting yourself down. In addition to making the game more likeable to people, it's also a good way to look at things in general. It was a Jam game. It wasn't made to be a masterpiece.