Why can’t the whole world have a universal currency?

A few nations, MNC's and people (Tourists) may profit by widespread cash idea, however not all nations. Each hopeful nation outlines claim arrangements and systems to manage GDP, increment ventures and so on. One of such methodology is degrading of money. Debasement helps in enhancing trades and decrease imports generously. But since of all inclusive cash, creating nations like India, China lose their possibility of surrounding and executing their own methodologies in accomplishing their objectives. In the event that we take Greece money related emergency situation for instance we can comprehend this absolutely. As Greece is an individual from Euro association, it doesn't have its very own money. So Greece couldn't raise procedures like downgrading, change of intrigue rates,at the season of emergency, to help their economy. What's more, everybody thinks about tricky outcomes they confronted

In any case, all inclusive money disposes of hypothesis on cash quality and enhances certainty. Part of organizations are beginning and spreading as a result of certainty on cash and national banks execution. Poor nations like Somalia get parcel of business trust as they receive all inclusive money.

Sure the world is becoming more open, in terms of trades and transactions. And countries’ economies are becoming more intertwined. There are few benefits of having single currency in the world, including ending currency crises and fluctuation risks. 

However, this idea of having a universal currency is not only challenging but also impractical on many fronts.

Different countries have different sets of rules, regulations, and policies. To that, they want to enjoy monetary independence.  Although all want stability, they have different short-term economic goals and priorities (some wants less poverty, others want higher employment). To achieve these goals, implementing or changing the internal policies might affect their global stand if sharing the same currency; or that the global monetary condition might affect their internal policy makings.

Look at the EU. The 17 countries share the same currency. And the financial troubles in Spain and Greece in 2010 are often credited to this.  

Another big challenge is forming a global body who will handle the policies and regulation of single currency. What are the chances they won’t go rogue. UN is already accused of prioritizing diplomacy over science.

So yes, as straightforward and appealing as it might sound, the idea of universal currency is flawed.