I only have a few UFOs but it's still more than I like. For me, the biggest factor is, by far and away, is that the most fun part of the process is the planning, designing, selecting fabrics and most of the piecing. The end of creating the quilt top, such as putting on set-in squares or triangles and adding borders is not as fun, but I'm pretty good at pushing through that. The remaining steps - deciding on quilting design, making a quilt sandwich and actually doing the quilting are much less appealing, so it's easy to procrastinate on tackling them. It's much more fun to run with a new idea and start working on that. ("I'm not easily distracted, it's just ... oh look squirrel!" This describes me more than I like.)