Most human economic activities are influenced by the need for money. But why can anyone not become rich?. What are the reasons why others work hard yet they are still poor? Why can't we print enough money for everyone? Questions like this do appear but there are reasons the answers are opposite.
If the answers to all those questions you asked can be answered, then we have practically solved say 98% of the world's problem while the remaining 2% will be due to greediness and non contentment nature of human beings. The solution to being rich is really not in the basis of working hard alone. Its a combination of several factors among which would include level of education, family lineage, the economic condition of the country and a host of other factors.
Printing money for everyone to be rich is just not the right answer because if we are all rich, no one would want to sell groceries, nobody would want to work in factories, no one would want to be cleaners to clean the streets or nurse who take care of the sick, the mechanic that fixes cars or the teachers that teaches our wards in school. Every unit and economic level exist to make the whole world habitable.