He basically thought that a perfect composition must consist of perfect parts.
What is valid for a perfect composition, holds true for practice and performance as well.
Every section, every measure, down to every chord, interval, and note in each voice.
Sounds impossible to achieve, doesn't it?
But we could try. When you look deeply into your practice, ask yourself, "is this the best I could do?"
Most of the time, of course, the answer is, "no".
PS You probably are wondering when to share it with the world, if it's still not perfect? Hint: when you run out of time or money.