Why are some handsome and beautiful children ugly?

I have observed this problem for more than ten years, and liberated my exclusive opinion on Zhihu for everyone to watch and comment. Hypothesis 1: human aesthetic concepts always think that hybrids are more beautiful. Hypothesis 2: In view of China's vast territory and numerous ethnic groups, children can be defined as "mixed-race" if their parents are far apart in ancestral home. The following is my inference from years of observation: 1. Most of the beautiful and handsome men I know around me have been investigated, and the proportion of parents' ancestral home is very high. 2. Decades ago, because my city supported the construction of the Northwest Third Line, a large number of immigrants came from Northeast China, Shandong, Henan, Shanghai and other places, so my post-80s classmates and parents came from many different regions, so a large number of mixed-race, handsome boys and beautiful women appeared, and the proportion was much higher than the normal level. 3. In first-tier cities such as Beishangguang, the proportion of beautiful and handsome guys is relatively higher. First, because beauty is also a scarce resource, it will flow to developed areas, and when the economy is developed, people will also invest more resources in dressing up. At the same time, there is another important factor: the population in big cities is more mobile, so the proportion of mixed-race children in the next generation is higher. 4. Negative example 1: Japan, friends who have been to Japan will find that the proportion of beautiful women in Japan is far lower than that in China. According to my own inference, Japan's territory is closed, and there are few opportunities for different ethnic groups to be mixed, which leads to the appearance of the next generation becoming more and more inconsistent with people's aesthetic instinct. The proportion of beauty stars in Japan is quite high. You can check it yourself. 5. Negative example 2: The appearance level of rural towns in backward mountainous areas with closed traffic is relatively low (without any discrimination), because, like Japan, there is a lack of mixed opportunities of different lineages.