Only some people are wired for it.
My wife is smart, hard-working, and has skills that would translate into much higher paychecks if she worked for herself. Even her hobbies could make her lots of money. I've tried numerous times to get her to start her own business, because I find entrepreneurship so fulfilling and I love the freedom and the challenges. I want to share the feeling with her and, frankly, I also want her to better understand me. Her complete lack of interest in starting her own business is so alien to me that we have really struggled to even communicate about it. I've bought her books and cut out articles of people that have started successful businesses in her field of interest in an attempt to entice her to the startup fold. She is completely not interested, and she gets tense and testy when I even suggest she start her own business.
One of her best explanations was that her very traditional, 'ladder-oriented' upbringing (father was a military officer, then a corporate man, and her mother was in academia) has made her most comfortable with a traditional job. She wants the safety and structure of working for someone else. Even if a startup would be more lucrative, fun, and flexible than her current job, her fear of the unknown outweighs those benefits. She doesn't want to have to always "figure out what to do next", and she doesn't want her income to be inconsistent.* She also needs quite a bit of external positive reinforcement for her emotional well-being (that is, she needs people telling her "Thatta girl!" when she does a great job in order to feel good and keep going.) She thinks a startup would be lonely and she thinks her self-confidence and motivation would falter without frequent external reinforcement from co-workers and supervisors. All of which is probably true.
Both of her parents are very educated (PhDs) and have always worked for someone else. They are also relatively wealthy. My parents didn't attend college, and are "rural middle-class," but they have both owned their own businesses. My parents also have some very wealthy entrepreneurial friends that I was around quite a bit as a child.
* I went from making $40K/yr working for someone else, to making more than that A MONTH working for myself. Even though I was making EXPONENTIALLY more money by working for myself, the income was sporadic, so my wife asked that I get a 'second job' making about $10 an hour as a 'backup'! She is completely emotional and irrational about money, and it drives me crazy.