ALWAYS GET FEEDBACK!

After and during each of the mentioned steps it's absolutely essential to get feedback. This can be from friends, co-workers or other members of the community via forums or by asking other artists directly. Don't be shy about this or feel like you need to do this on your own. Especially in a professional environment, the motto is to fail fast so that you can learn early. Big teams always seek and give each other feedback so that the end result can be the best it can be, and truly great results are rarely from just one mind alone.