The answer is "China's standard of living has increased, and workers are requesting more pay."
China has the quickest development of utilization of any nation on the planet – whether this is estimated just by family utilization or incorporates government utilization on territories indispensable for personal satisfaction, for example, instruction and health. China's personal satisfaction is superior to would be normal from its present phase of monetary advancement. Clearly, income is just a single part of expectations for everyday comforts, while the typical cost for basic items is another. Given a settled level of salary, the higher the average cost for basic items, the lower the expectation for everyday comforts. That is why workers are requesting more pay.