This reminds me of my all-time favouries quote, which I believe originally came from Mark Twain. To paraphrase:
'When you grow old, it is not the things you did in life which you most regret; it is the things you didn't do.'
It's so true in my case. If you do something in life and it goes wrong, well, at least you tried and learned from the experience. But if you don't do something exciting or adventurous out of fear or uncertainty, then you may always wonder what might have been, if only you had had the courage.