The production of infant formula in China there are more than 130 enterprises, and only four companies in the United States, compared to the United States for the number of infant formula milk powder is much higher than our country.  imagine, if there are only four production formula, the enterprise will cherish their own brand value, continue to strengthen food safety consciousness, any possible food safety risk is the enterprise itself, It would be unthinkable to occur a problem with melamine. 
There are too many enterprises producing infant formula milk powder in China, brand value is not important to the enterprise, so these enterprises dare to add melamine in milk powder weakens the above view.