Net worth: $49 billion
Was born in unfortunate circumstances to a single mother. His mother didn’t have the means for a child, so she had to ask relatives to raise him. Ellison later had to drop out of college after the death of his adoptive mother when he was forced to take a bunch of odd jobs to make ends meet.
Later, he was accepted at the University of Chicago, only to drop out after a semester as a result of low grades. He eventually found a job as a programmer for Ampex Corporation. In his own words: “I never took a computer science class in my life. I got a job working as a programmer; I just picked up a book and started programming. I was largely self-taught.”
At Ampex, he found his calling of working on enterprise software where he worked on a project that would later become the multibillion-dollar database management giant Oracle.
Success Habit: “The most important aspect of my personality as far as determining my success goes; has been my questioning conventional wisdom, doubting experts and questioning authority. While that can be painful in your relationships with your parents and teachers, it’s enormously useful in life.”