If you're waiting for a boss or an editor or a college to tell you that you do good work, you're handing over too much power to someone who doesn't care nearly as much as you do.
We spend a lot of time organizing and then waiting for the system to pick us, approve of us and give us permission to do our work.
Feedback is important, selling is important, getting the market to recognize your offering and make a sale--all important. But there's a difference between achieving your goals and realizing your work matters.
If you have a book to write, write it. If you want to record an album, record it. No need to wait for someone in a cubicle halfway across the country to decide if you're worthy.