Response: Because the natural attraction of men and women are different. Men and women are not the same emotionally and psychologically, so attraction is also different. Women are naturally more sensitive and less inclined to fight. Men are less sensitive and more inclined to fight. So because women are more sensitive, it takes much more for a woman to be aroused. Men are not as sensitive, so it does not take much. Men are more visually aroused, which is why the restriction of modesty is more on women.
Yet this serves as a benefit for women because that means that since men are not naturally sensitive, then only through the modesty of a woman can a man be utmost in compassion and sensitivity. Without it, no man can attain it because by nature, men are not naturally inclined to be sensitive and compassionate. That means that a woman can use her modesty to influence and control a man, which means a woman is truly the woman who can influence the society.