"I wish I knew that sooner."
Every entrepreneur has said this.
When you wait too long to get your idea out there, you only learn a bit. And by then it's too late.
"Launch fast and iterate" - Paul Graham, founder of Y Combinator
When you launch the fastest thing you can, the more time you have to try again. Trying again and again, you learn what's important so your next decisions are better each time.