They practice and observed how the fluctuations will favored them, I think its really in need for us to be that way, if you are serious and you really wanted to take it seriously, then studying and not giving up would be the key to succeed, treat this mistake as another way to learn, many people who take the challenge succeed after several mistakes, I still believe in those saying that never gives up till you still the plan and you are still alive take the challenge and win it by your hard work and dedications.