Not knowing how to "do" a project has never stopped my from starting. But it does stop me along the way to finishing. Like not knowing how to do the binding as someone mentioned. One quilt took 5 years: first to find the perfect fabric, then trying to redraft to block, then knowing something was wrong and couldn't determine what it was, redraft the block again, then needle turn applique 8x12 exactly the same pieces (got so bored, really had to persevere). I love to challenge myself, but I need other projects going at the same time. Lately I've discovered that when I'm stuck, making fabric post cards with whimsey helps me get going again. I do try to avoid UFO's in other areas of my life.