smm responded with numbers. But intuitively, you can compare the efforts needed to immigrate: crossing the border in the desert, or crossing the ocean. Even in

smm responded with numbers. But intuitively, you can compare the efforts needed to immigrate: crossing the border in the desert, or crossing the ocean. Even in the case of an immigrant with a low level of education from a poor background, there needs to be a group willing to make him/her cross the ocean. So from the start (s)he will be have been selected as worth the cost of the plane ticket, and will be integrated in a community/somewhere as soon as (s)he lands in the country to make up for the initial cost.