How I Rebounded After Nearly Flunking Out of CollegeShame that you let down yourself and the people who have faith in you is a powerful motivator.

我差点不及格的大学。没有太多的不le know that. It's not a secret – just not something I'm particularly proud of. And since I rebounded nicely in grad school and my career took off from there, it's never really come up.

Why bring it up now? Had I not taken that wild rollercoaster ride then, I would never have learned the most important lessons of my life. I would not have ended up where I am today -- and that would have been tragic.

I left home and moved away to college at 16. Too young. To say I wasn't ready for the responsibility of being out on my own is a major understatement. I succumbed, all too easily, to the lure of sex and drugs and rock & roll. I know that's cliché, but that's what happened.

At first it was fun, but as I slid down that slippery slope of cut classes and late night partying, fun turned to failed tests, lousy grades and depression. At one point I was sleeping away most of the day. Finally, it happened. I failed a class -- the first of my entire life -- and ended that semester with a dismal 1.6 GPA.

At that point, you would think I finally bottomed out. Nope. There was much more pain to come. It took another semester just like that one before I finally realized that maybe I was done. Finished. Washed up before my career even got off the ground.

I called my older brother to talk it out, and that's when a strange thing happened. Once I heard myself say it out loud, "I'm thinking about dropping out," that was the bottom. I was so ashamed of myself, I just couldn't do it. Instead, I decided to look into switching majors.

Turns out, I was premed for the wrong reason -- because my parents wanted their son to be a doctor. But when I searched my soul for what I really wanted to do, the only thing I could think of was astronomy. I'd always had my head in the stars.

The head of the astronomy department was far more practical, though. He advised me to major in physics and keep my options open. It's a good thing. I fell in love with physics. Yes, I know how strange that sounds, but it's true. Just one problem, though. I was good in math, but no Einstein. I finished my degree with a dismal 2.8 GPA – not nearly good enough to get into a decent PhD program.

What saved me, of all things, was a girl. Her father ran a high-tech startup, and he advised me to go back to school and become an engineer, so that's what I decided to do. Electrical engineering turned out to be a piece of cake compared to physics. I sailed through grad school with flying colors, landed a job in the tech industry and eventually became a top executive.

Looking back on it, that experience taught me three important-but-counterintuitive lessons that have stuck with me all these years and played a big role in my success.

Related:Why We Balance Passion With Reason

Shame can be a powerful motivator.

Today's popular wisdom says that you should be happy the way you are and never shame anyone else for being different. I have no beef with that. But if you screw up and make bad choices, sometimes the only thing that brings you out of a tailspin is the shame that you've failed yourself and those who have faith in you. I expected big things of myself, as did my parents, and I wasn't about to let us all down.

Related:Move Away From Shame-Based Management to Inspire Productivity

When it comes to advice, consider the source.

Bless their hearts and good intentions, my folks pushed me into medicine because that's what they wanted. Never mind what I wanted. They were too close to the situation, so their viewpoint was skewed and their advice unreliable. The astronomy prof and my girlfriend's father, however, had no skin in the game. They were objective, so their advice was what was best for me, not for them.

Related:A 3-Step Technique for Deciding Which Advice to Follow

Follow your passion, but keep your options open.

It's said that, if you love your work, you never work a day in your life. That's true, but you can have more than one love. While my first passion was astronomy, had I not been adaptable and kept my options open, I probably never would have discovered all my other loves: physics, high-tech, sales and marketing, writing, and of course, my wife Kim, who I met along the way.

One last thing: As long as you have reasonably high expectations for yourself, never give up on them. It ain't over "til it's over.