I agree with smart trader that it can be a lucrative career only if one works hard and smart. No degree and earn more than $10k a month is very common in singapore. I remember there is an article in salary.sg about hawkers earning >$100k a month in sales. Even after say 50% expenses, still can make $50k a month. Maybe they don't even have PSLE.

I believe the higher your education, the less you will start your own business, therefore less chance to become rich. Being employed and earn $5k a month is good pay. Being self employed and earn $20k a month is normal.