Michael Dell, Bill Gates, Mark Zuckerberg, Larry Ellison are all famous college-dropout billionaires. Check out this list for the full number of some of the most famous college dropouts. The combined net worth of  the most famous dropouts is USD 246 billion. The average net worth of billionaires who dropped out of college, $9.4 billion, is approximately triple that of billionaires with Ph.D.s, $3.2 billion.

According to a recent report from Cambridge-based Forrester Research, 20% of America’s millionaires never attended college. Make no mistake, for most people advanced degrees are still valuable. A graduate degree can have a huge impact on your household income and your life progress. A family with a professional degree holder can make 5X of a family with just high school certificate holders.

The question then is; why are so many college dropouts successful in life? It’s true there are successful college dropouts. It’s also true many more fail. Here are a few reasons (most upvoted) as shared on Quora, why some college dropouts are successful in life and or business.

1. A dropout has no plan B. You don’t have a degree or a guaranteed job to fall back on. So you push yourself harder. I do feel I did so myself, when I recall my young years and those of my batch-mates.

2. A dropout starts earlier. I started my first business at 18 and failed. I started my second months later. And failed again. I then started working for others. And by the time my cohort had graduated, done their masters, etc. and come into the real world, I had already worked for 5 years and they came in some 2 rungs behind me on the same corporate ladder.

3. A dropout has fewer fears, loans, expectations to live up to. My dad expected i’d end up waiting tables at a Udipi restaurant. It was not difficult to surpass this expectation. I daresay my friends who did the Engineering + Masters route had higher expectations to live up to.

4. Depends on why they dropped out.  A book “The Millionaire Mind” covered this topic in great detail. In short, (from the book) dropouts CAN (but not always) be more successful because they develop a thick skin to failure and are able to pick themselves up faster than the straight A honor student.  Ever see how life smacks a straight A student in the face for the first time and they are paralyzed (mental of course)?

5. Richard Branson, Mark Zuckerburg, David Karp, Bill Gates……are people who went on to become billionaires with little or no college education. These people are outliers of the population – through their domain knowledge, personal networks, work ethic, and also just good timing, they went on to become uber successful with their careers as business owners.

6. The “thing” that separates successful dropouts from unsuccessful ones, is the successful ones do not dropout of learning and doing. They simply take a different route to achieve a common goal.

7. College doesn’t make you successful or teach you things you cannot learn elsewhere. It is simply a stamp of certification and if you graduate it shows that you can commit to something and complete assigned requirements.

Most people should go that route if you’re looking for a “white-collar” job. However, there are and always will be, people with different skill-sets, mentalities and preferences. You don’t have to change the world to be considered successful, nor do you have to complete college.

8. They were hungry. Steve Jobs mentioned hunger in his commencement speech at Stanford. These successful dropouts had a hunger to learn. John Mayer’s favorite part of high school was the moment he could go home and imitate his rock legends and study their body of work. Studying their lyrics, the melodies, the riffs.

9.  They were relentless. Whenever you learn something new. You will fail. And then when you become successful at some point you will fail. Failure is inevitable, but why can’t success be inevitable? To succeed you have got to have GRIT. It really isn’t about how many times you fall but how many times you get up.

10. The Harvard dropout success stories are the geniuses, identified and admitted by Harvard, who got too bored to wait around getting a credential for 4 years. In most cases, they were smart enough to make the calculated decision and realize their ventures were about to pay off bigger than the Harvard degree.