I have researched a bit in different forums.
Main answers include: 1. So Different countries can control different monetary policies 2. So different countries can handle shocks(up and down). 3.Based on region,human resource, natural resources, geographical position, cultural diversity, ethnicity etc
1.My question is why not control money as if there is a single country (with more than one states(suppose each state is a country))?
2.Why currency will be divided based on region,human resource, natural resources, geographical position, cultural diversity, ethnicity etc? (states/places in a single country can also have diversity then how they can be managed and several countries cannot be managed?)
3.Because if that is the case who decides we need different currencies based on which conditions (eg. eurozone)? If the division is true why not there are different currencies for each 10-20 kilometers(or where there is more rice growth,or where there is no agriculture but more tourism difference based on these differences)?
Edit : please don't make it duplicate because I am asking after seeing the other questions. After checking now I want to know more derived from that answers.. please refer q 2,3