Fear of failure kills progress. Too often, I've found myself in a state of paralysis because I was too afraid of failing. There's a long list of song ideas I didn't record, story ideas that I didn't write, girls I didn't ask out, and opportunities that I didn't pursue, all because I was waiting for "right time". The moment when all of the variables would be in my favour so there would be no chance of failure.
It took me a long time to realize that finding the "right time" is rare and failure isn't an enemy, it's a teacher.