Get your product into the hands of customers as soon as possible. Engineers, by nature will tweak the design until it’s perfect. If you wait, you could spend a lot of time and money to find out customers won’t pay for it, or worse, you’ll miss your market opportunity altogether.
If your idea solves a big problem, chance are that someone else is trying to solve it too. Don’t let them beat you to your customers. Release the product when it’s just good enough. Your customers will help you with the rest.