I think everyone has their own definition of UFO. If I have a pattern & pulled the fabric, that's just a pile of fabric. After I've cut the fabric and am actively working on a top, that's a top in progress. If I don't work on a project for a while (after the fabric is cut) it becomes a UFO. The amount of time "A While" is varies by season. When the top is pieced, but not quilted, it's a completed top, not a UFO...
Look over all your in process projects. If you really don't think you are going to finish something, and that bothers you, then by all means donate it. A local guild may have a charity quilt group that could take it & finish it.
I would find the one that is closest to completion and work on that one get it done. That will give you a sense of accomplishment and hopefully encourage you to tackle the next one.