In addition to the valid reasons mentioned by others here—English ability, labor shortage in Japan, less of a hacker culture, etc.—there is also a difference in

In addition to the valid reasons mentioned by others here—English ability, labor shortage in Japan, less of a hacker culture, etc.—there is also a difference in attitudes and expectations about employment. Many young Japanese prefer to work as full-time company employees, both for the stability and for the social status. My younger daughter graduated from a Japanese university twelve years ago and has been working as a systems engineer for an IT company in Tokyo ever since. She told me recently that, of the thirty-five people hired at the same time as her, only three or four have left the company. My daughter expects to work there for the rest of her career. Freelancers here are more likely to prefer working for clients in Japan, too, as there is less hassle about payments and clients may be more reliable. I freelanced as a translator for twenty years in Japan, and over thousands of jobs from dozens of clients I had trouble getting paid only once. In contrast, complaints about nonpaying clients were a constant refrain among translators I knew in the U.S. That said, in my semiretirement I recently started doing a little consulting work for an IT company in the U.S. Once we got through all the hassle of identity checks and bank transfers, I have been very impressed by the speed and smoothness of their payment system.