How easy is it to “hit it big”? What are the pitfalls of starting your own business?

Is the belief among Yeshiva bochurim that making money is easy — fact or fiction?
According to Halacha, what happens when business partners fail to discuss equity upfront?
What if one partner works harder or originally came up with the business idea — how should that be handled?
Can you start your own business while working for someone else — and what if it’s competitive?
What does it really take to succeed as an entrepreneur?