International trade and exchanges are generally carried out in USD, Euro, CAD, AUD, GBP, Swiss Frank and JPY and USD is most preferred. There are exchange rates for all currency pairs like yesterday 1 USD = 63 INR. When your company want to cash out the profit from Indian branch, you have to surrender the amount in rupee to Reserve Bank of India who will give you equivalent amount in USD so you have USD. Similarly for most international transitions, while importing payment is usually made in USD to supplier by say RBI ( for India) and local consumer will pay only in local Indian Rupee and exporters have to surrender the amount to RBI and they get local currency.

only if the value of the currency is fixed and there is no reason to alternate production sites

having a number of alternate locations (foreign and domestic) provides flexibility on where to produce at the most advantageous cost

with that in mind, the most advantageous cost could be due to currency fluctuation alone and not labor, for example

Suppose a company is headquartered in USA. This company has put 5 manufacturing locations in India as branches under foreign direct investment. Now, if I am a buyer in India,I will buy something from this branch in India through our local currency,rupee and not dollars. For example,if the branch manufactures cars,then I will be buying a car for say 6 lakh rupees.This will help our local trade.So a buyer in India has contributed 6 lakh rupees to the company which will flow as profit back to the U.S ( As the main office is located in the U.S )

If the same company which is in the U.S,manufactured cars for customers in the U.S itself,then buyers in U.S will transact in their local currency,dollars,thereby benefiting the U.S economy to a far greater extent when compared to trade in rupees back in India. So why should this company come to India to invest at a loss to service Indians.They are essentially sacrificing their profits . Are they not ?