push factor

— The push-pull hypothesis proposes that people will voluntarily vacate old premises and seek new ones when conditions are no longer comfortable or tolerable, or when conditions in another country offer more favorable circumstances for an improved standard of living. According to Juan Gonzales (1990), immigration to America reveals both of the aforementioned push and pull factors. The push factors include economic conditions, political conditions, social conditions, overpopulation, and natural disasters. […] Political push factors include such unsettling events as rebellion, revolution, war, and seizure of the government—all of which reflect grave instability in a society.