By Paul Hackshaw
The Japanese government has been throwing everything but the kitchen sink to try and get people to move here. The language barrier is the biggest, second is most visas are for individuals and family migration is discouraged. There is simply not the support to bring spouses and a whole bunch of kids unless you are a well compensated ex-pat. Finding childcare for working mothers is a huge problem in Tokyo right now.
Stringent visa rules. Must have a degree or qualified or have relevant skills. Japan most needs people in child care, elderly care, construction. Not things that lend themselves to people with a college degree.
The hidebound work culture. Most foreigners are expected to fit in with whatever their company culture is like, including long hours, long interminable meetings. Long commutes, and the different ways people communicate with each other, Senpai-Kohai relations etc.
Japan is a little rock on the edge of the Pacific and a long way from anywhere. Hong Kong Singapore etc. Westerners prefer to work somewhere they can speak English and bring their families.
Source: Quora