Ok--feedback is BAD when you're recording (unless it's guitar feedback, but as a guitarist, I'm biased), but GOOD afterwards. I mean, of course, the kind of feedback provided by a happy client or an enthusiastic audience.
But if you aren't getting feedback? How are you measuring your performances?
We all can think we're doing a great job, chugging along with the same techniques that we've always used. But are we keeping up? What's being innovated around us that we might be missing out on?
The truth is, feedback IS all around us, even when we're not getting it kicked back to us from clients or listeners. How's your response rate to auditions? How many calls are being returned? What do your sales look like or how many people from your mailing list are turning out to your shows after you announce them?
It's important to stay fresh, and keep challenging yourself by setting measurable 'feedback goals'. If your clients aren't giving you what you need, how about a nudge? A site like SurveyMonkey lets you set up a short questionnaire they can answer anonymously at their convenience, giving you the metrics you need. You can also put it on your site or social profile, letting casual listeners give you some hints, too.
And, most importantly, listen to your gut. Do you KNOW it's time to start doing something different? Are you still challenging yourself to learn a new skill or take a risk? Be critical of yourself and your performances and work habits, but also follow your instincts. You know your abilities--put them to the highest use!