This was on that link
"The bonus will attract the labours to work harder and increase their effort to compete each others where it makes the production of the company growing up. While in United States, to those who already worked with the company in long period, I will asked them to choose either want to work in Mexico or United States. If they choose to work in United States, then they would be in the position of design function and other management duty, not in the production anymore..."
Hmm...