You should always be improving. We don't live in a stagnant world. Your business shouldn't be stagnant either. You should continually be improving your business because it is best for your customers, your employees and you.
But have you ever thought about other businesses being better than yours? Have you been concerned about them exploiting your areas of weakness or finding a way to serve people better than you do?
If so - good. That means you care.
Fortunately, you have more information about your business than your competitor has about it. So you're in the best position to improve it before they find out what is the matter with your business. You just need to keep on it. Keep showing up. Don't let your fear or ego get in the way.
Keep going. Your consistent effort might be preventing business disasters you didn't even know were looming. You're doing it Peter, you're doing it.
On a slightly related note...you're no different than Robin Williams (you are, but you're not).