How to Stay Motivated & Finish What You Start

How do you stay motivated to finish that project you've started, once begun?

That is the question. For 2 years now I haven't finished any manuscript I've started. The most I've written was half a novel. Like 20,000 words then just abandoned it. The last manuscript I abandoned was 3000 words long, but usually my projects get tossed aside after a few hundred words.

Maybe if I blog about it I can brainstorm my way into finishing what I start.

Let's figure out why I get unenthusiastic at what point in ...