Shortage of girls
Dearth of eligible female partners
In China, bachelors were found to outnumber single women by 10 million within the 29 to 49 year-old age group (based on the 1982 census and a 1987 survey). In Korea Rep there will be a 120 men per 100 women in the year 2000, because of the traditional preference for boys. According to a 1993 study, the increasing financial independence of Japanese women (approximately 50% of women in Japan work outside the home) has propelled a power shift in marital affairs. According to the survey Japan claims approximately 10 bachelors to every 8 marriageable women, many of whom are less interested in marriage today than in previous years. In the USA for every 100 unmarried women aged 20 through 29 there is 122 unmarried men in their 20s, but this situation reverses for women over 30.
There are enough women. But men don't want to marry women who are successful in business. If a women earns more than her male partner, he becomes jealous and feels threatened.