There is no end to good design.

Onur Cobanli explica:
If you really want to do your best design, you must accept your good design as is; there is no end in reiteration, improvement, making it better, adding a few more details, making a few more refinements; design never ends; there is always, always something better your can do, but you must accept the most important restriction; time. You might say, that there is absolute best form of a product, and I say that there never is, as such a product cannot exist; here is why, let's imagine you created the worlds best product that solves a particular problem, it is simply best, right, without reservation, so you think you cannot improve it further, but what about a product that is so good, so magical, so advanced that it makes itself unrequired by making the initial problem non-existent; i.e. products are all to solve and respond to a particular need or problem, imagine a product so advanced that it simply eliminates the problem rather than being a tool that is used to overcome the problem, it is not only scary, but it creates a logical fallacy; since the perfect product would remove itself from existence by making the problem for which itself was designed as a solution for non-existent, it cannot exist itself. That's aside, I actually deviated from my initial idea, what I actually mean is that no matter what you do, there is always something more you could do, provided there is time, there is no end to designing, so simply give yourself a time-frame, and move forward; do your best, introduce your design to the World, and perhaps later work on a newer version, do better, do more.