I used to think that 'd love to be able to finish one project at a time, but not now. Either something that NEEDS to be done comes up or I see a project that I just HAVE to do. I used to let it bother me, but now I look at it a bit differently. I've decided that it's really a blessing to have things at different stages of completion because I always have something to work on, based on how much time I can commit, or what I want to do.
For example, if I feel like quilting, there is always a project or two (ok, really 10 or more) that needs quilting. I get to choose which project to quilt and can get to it right away because I try to have the backing and batting prepared and with the quilt. Also, it's very rarely that when I finish quilting a project that the binding doesn't immediately follow. I get so excited when the quilting is done and I really do like to bind.
Sometimes I just really need to work with bright colors and not Civil War reproductions or others because those fabrics make me smile. If that's how I feel, I go a tub with those type of projects and woo-hoo, I'm good and life is good!
There are other times that I'm really busy and life gets in the way of quilting, there's always a project that allows me to sew for just a few minutes at a time and give me a quick "fix."
Maybe it's just making excuses, but this works for me.