I'm with you- really bad at finishing them. I go like a maniac and then get bored with the one I'm working on, especially if it's not turning out as well as I would like (like the one I'm working on now, a zillion things to match up at every stage) So......... I end up with too many tops.
The sorta good news is when I leave them for awhile my interest becomes renewed and they look better than I remembered so then I finish them!!! :D