Source? I have a different viewpoint, a lot of people have national pride, still have a better network back home, or their parents' business, so that they actually go back to work in their home countries.
I'd say it depends on the quality of life in the student's country. Those from western Europe, Japan, South Korea and Australia and any other country with similar quality of life would not mind going back, but almost everyone else would rather stay.
Generally, I'd agree, although in come cases plans just change: A foaf of mine from Japan studied in Vienna. After graduating, he decided he didn't want to permanently go back to Japan's rigid social structure. So he decided to stay in Austria. (He later married my friend's sister.)
