Well I don't think one necessarily need to be a victim of failure before learning, you can learn from history of someone else, it maybe failure experience or success.Yes brilliant failure is the best teacher if you don't failure you still wont know how to succeed.
In order to reach your ultimate potential, your personal best and to make the ‘impossible’ possible, you need to push yourself, go to the absolute limits and definitely not fear failure. When you have a no fear attitude and embrace failure, it will maximize your motivation, determination and perseverance.