I'm not sure if it's absolutely necessary to set out to fail, but at the very least, you need to be willing to land in the mud every once in awhile.

As Seth Godin points out, "Think about how often your goal at a conference or a meeting or in a project is, 'don't screw up!' or 'don't make a fool of yourself and say the wrong thing.' These are very easy goals to achieve, of course. Just do as little as possible. The problem is that they sabotage your real goals, the achievement ones."

If you're satisfied with mediocrity, then do just that: set yourself to achieve safe goals like avoiding embarrassment. But if you want for yourself even something slightly better, don't be afraid to stick your neck out, doing whatever it is. This advice isn't anything new. You may have heard...

"Shoot for the moon. Even if you miss, you'll lad among the stars."

"Believe and act as if it were impossible to fail."

"Success comes to those who are neither afraid to fail nor discouraged by failures."