The British collected a number of Nepalese youngsters to the British armed forces. And they collected migrants to come and work for them. They used the migrants of Nepalese for employment purposes only. There are many villages in Nepal where labor migration has been established as a culture of a community.
Economic migration to the Middle East from South Asia and other parts of the world was spurred-on by the oil boom in the early 1970s.

Why do they need migrants to work for them?
How could they end migration?