Perfect is a nice idea and a terrible deadline.

Perfection is a fine direction and a hopeless finish line. As a standard it keeps you improving; as a deadline it guarantees lateness, because there is always one more pass available and nothing that tells you to stop. Most unfinished work was not abandoned, it was polished past the point of being useful. On time and good beats flawless and late nearly every time.

Decide in advance what finished looks like for the next thing you make. Write that stopping point down before you begin. When you reach it, hand the work over even if you can still see a flaw.