Everyone's afraid of something. Personally I'm afraid of snakes, heights, and poor writing (so you can imagine how I felt about Snakes on a Plane!). But failure has never bothered me much. In fact, I'm kind of a fan.
I worked in sales for a good while before I became a cartoonist, so I got very very used to failing early and often. The way I see it, the more you fail, you the closer you are to figuring out what works.