This is the spirit of [[Kaizen]] from Lean. There is no perfect process, no perfect design, and not perfect user story. You can, however, perfect your processes, your designs, and your user stories. Improve not by waiting for perfection; Find a starting place, get started, and improve continually from there. [[Feedback]] cycles combined with [[Reflect Regularly]] allow you to do the best you can do today, while striving to do even better tomorrow, much like [[Kaizen]] in Lean.