Why currency didn't standardize?

Question

I mean Euro, US and Asia currenct at the same rate?

Why Pound sterling is more expensive than Euro and US?

Answer 1

Why would you expect them to be standardized? They are all separate currencies created by different countries at widely different points in history. Do you expect the native languages in all these countries to be the same too?

The Euro, as the most recent creation, was indeed originally issued on par with the US dollar, but aside from that there is no reason to expect any similarity in values of different country currencies at all, nor is there any reason for governments to attempt to match their currency values just to avoid confusing people like you who seem to have difficulty with this.