I've done it...I have a cross-stitch started that I have no interest in finishing. I also sew and have a coat that I made, but I don't like it at all. I can't get rid of it as I entered it in the County Fair and it won best of show. Since I dislike it, I think I will display it and it's ribbon on a dress form.
So, I have great experience in not finishing something I don't like and finishing something that I don't like. :-)