Musical completeness. How do you measure it?

A question for composers or arrangers:

Let's say there are two interchangeable phases on musical creation.
Composition and checkout.
In composition is everything that helps developing the work. Checkout
is the point where one sees the product and decides going back or
determine the work as complete.

What is/are your method(s) for this? If it is an ordered work, it's
based on functionality? but, what about personal works?

Thanks =]