To me, a UFO or WIP is anything that cannot be used for what it's being made for -- placed on a bed (quilt), wall (hanging) or table (topper), worn (as a garment) or carried (as a bag or tote). Everything goes in stages. First it's pieced, then it's layered, then it's quilted, then it's bound. Once it's ready to use, it is no longer a UFO or WIP.
This may just be me rationalizing it, but it keeps me from going crazy. I actually prefer the term Work in Progress, because then I just figure what stage I'm in.