I think when our excitement on a work dies away, it's time to shelve the dang thing.
What do you do? Do you have to be completely passionate about your work, or is it more like a job to you and you just fight to get it done and out there, even if the passion dies away? (I'm not talking about the "first-draft lust" type of passion - just that deep love for a work that drives you forward).
Maybe I'm only being distracted by shininess elsewhere. That's entirely possible. Ugh.