Foreign reserve will definitely run out in long term?

binocular222 asked: Let’s talk about foreign currency inflow-outflow at developing countries:
FDI,FPI: When foreign investor invest in a country, they expect to earn more than what they paid which means in long term, when they withdraw principal+profit => foreign currency OUTFLOW is greater INFLOW
Loan (commercial loan, ODA, IMF, WB…): In long term debtor has to pay [...]

What affects a country’s currency and its exchange rate?

Alyss asked: What can affect a country’s exchange rate and currency value in relation to foreign trade?