Part of making good decisions in business is recognizing the poor decisions you've made and why they were poor. I've made lots of mistakes. I'm going to make more. It's the name of the game. You don't want to expect perfection in yourself. You want to strive to do your best. It's too demanding to expect perfection in yourself.
One of the biggest mistakes companies make is brute force lead generation - "give me more leads!" -when they don't understand that not all leads are the same.