What “success” means is open to one’s own interpretation, but hopefully it means you will love to ride your bike for the rest of your life. We gotta set one thing straight right off the bat, bike racing is HARD and becoming a professional bike racer is even HARDER. I've heard bike racing compared to slamming your hand in a car door for “x” amount of time. And as Greg Lemond said, “it never gets any easier you just get faster”.(hopefully)
When it comes to being a professional bike racer (on the MTB side in Canada and at any point in time), there have been more people walk on the moon than spots on teams that will allow you to race and have something in your pocket when you finish the season. Being a professional rider means way more than just riding and racing your bike and could be whole other blog post but in short you are a salesman/woman.