1. It’s good enough. You’ll tell yourself it’s “good enough” when you’re tired, frustrated, or lazy. The problem is that everyone is “good enough.” Good is average, mediocre, barely hitting the ball out of the infield. Jim Collins opened his bestselling book Good to Great with this sentence: “Good is the enemy of great.” You can’t do something that matters if you settle.

2. It has to be perfect. This is the flipside of #1. The perfectionist wants to keep tweaking until everything is precisely right. Perfectionism, however, is a stalling tactic, an unwillingness to commit. Could you make it better in another week? Maybe. But then you’ll want to spend another week to make it better still, and another week after that. Better is the enemy of best.

3. I can’t do it. What makes you think you’re so smart? Who gave you permission to do this? At some point, behind every entrepreneur’s big idea, every aspiring author’s novel, every dreamer’s vision is the nagging doubt that they don’t have the stuff to pull it off. This is the resistance, the lizard brain, the flinch. Don’t listen. Take a risk. Take cold showers for a week. Face the flinch and act.