If there are rich people, poor people go on working. If there are only poor people, poor people go on working. But if there are no poor people working, there will be no rich people. So, people become rich if poor people work.
There are individual oriented work that can make people rich. Sports persons, film stars and models, eminent lawyers, artists and so on! This principle doesn't work with those people.
Where money is earned by combined effort of many people, naturally talented, skilled and learned people with originality who are scarce in society earns more. Manual unskilled workers are available and less costly, they earn less and remain poor. This issue has far more depth than just a rich-poor matter.