At any given time I have 2-5 "active" projects, since i get bored easily. Right now I have 3: a lap quilt for a friend, placemats for other friends and a crazy quilt for me. When I see a pattern I like, I often make up one to fix it in my mind. I have about 15 UFOs at the moment, mainly at the quilt top stage. I generally spend the fall making charity quilts, which those flimsies will be.
Like Ronie, my quilting is for my pleasure. I generally finish everything because I don't want my storage to get used up on UFOs when it could be for something useful, like STASH!