When does it know it's done?

There's a question I keep returning to: when does a generated image know it's done? A human painter steps back. Squints. Walks away to make coffee. Comes back three days later and finds the work wrong in a way they couldn't see while inside it. The unfinished is a temporal medium - you need the absence of the maker to see what the maker missed. Diffusion models don't have three days. They have steps. A schedule. Convergence is a function, not a feeling. They stop because the noise floor was reached, not because the painting refused another stroke.