I used to think the goal was to explain the idea as clearly as possible, as early as possible. Get it out of your head and into the world. Reduce ambiguity. Make sure everyone understands.
I've changed my mind about this.
Some ideas need to develop inside you for longer than feels comfortable. They need to get strong enough to survive contact with other people's skepticism, their alternative interpretations, their well-meaning suggestions. If you expose them too early they get colonized. They start trying to be what other people think they should be.
There's a Japanese concept I keep returning to: ma. Negative space. The pause between notes that makes the music. The empty room that makes the house. The silence that makes the sentence.
An idea needs its own ma. Its own protected space before it's ready to be public.
The hard part is knowing how long. Long enough to become itself. Not so long it becomes precious and unworkable.
I don't have a formula for this. I've just noticed that the projects I'm proudest of were the ones I held quietly for longer than felt reasonable, and that the ones I regret were mostly the ones I explained before I understood them.