The way I understood the original submission was that "100%" indicates the point where the thing is ready to be released to the world at large. Before that, one may well do iterations involving users and potential customers. That will of course make the actual release, or launch, less of a traumatic event. And yet, perhaps I'm old-fashioned, but to me, release is still an important milestone, sort of a finish line, or a goal I'm working towards. That "first 90% vs. last 10%" really resonates with me.