There are limits to what you can sell in China and to grow your business there the Chinese require you to build factories and take on a Chinese partner. It is the way they segway themselves into new technology (forced appropriation).

Many companies understand that it is the only way they will be granted access to the Chinese market and try to innovate outside of the country staying ahead of what technology the Chinese will eventually steal.

I have some personal experience with this since a technology company I worked for chose to close it facility in China due to the incessant theft of their IP. The Chinese Military had infested the factory floor and were using the Computer stations on the line in an attempt to hack the corporate network and interestingly enough our financial department. It was constant and every time you caught an employee hacking, they would just walk out without answering any questions.