Why people need more and more mony ?

Answer 1

I am not sure what your question is. As an economist, as the world becomes more productive, this drives the need for more money to support the increased production. Money itself isn't very valuable. Little scraps of paper and metal discs really are not valuable. However, as they buy production from others, they are quite useful.

Answer 2

Because there is unemployment in your country and if you have enough money then you can hire a Driver, Chef, Trainer, Bodyguard, Portfolio Manager, Lawyer, Medic...