Birds herd around places of water and trees, sheep flock around places of water and greeneries and so also human race, then.
But educated modern humans migrate around places where better opportunism for better papers (currencies) are available.
Individuals migrate for better pay & perks! Families migrate where there is rule of law, guaranteed personal safety and where meritocracy is the norm!!
Half truth.
Many people migrate to Gulf countries Where there is no democracy, no guaranteed personal safety.
Incorrect statement... Mostly blue collar workers go to Middle East without their families! It is only the white collar workers who go with families to safer places in Middle East such as Dubai! To Saudi even officers hesitate to take their families!!
Foreign born as % of population, 2014
Dubai: 83%
Sydney: 39%
Los Angeles: 39%
Singapore: 38%
London: 37%
New York: 37%
Paris: 25%
Source: The Int'l Spectator