I'm not sure myself, but I'd wager it's when the brainstorming and iterations are getting less significant. When you're changing less and less through each iter

I'm not sure myself, but I'd wager it's when the brainstorming and iterations are getting less significant. When you're changing less and less through each iteration, then you know it's getting close to being done. That being said, at some point someone (preferably someone wise and smart) makes the decision to ship. And they do need to make that decision.