It isn't, still the global sums now exceed $300 billion a year. India ($27 billion), China ($26 billion) and Mexico ($25 billion) are the leading beneficiaries. Some small countries increasing their national incomes by more than 20 percent. Egypt gets more from remittances than it does from the Suez Canal.
But when I ask you to name a single country that has developed through remittances: the answer is no — there's none.