What kind of people are easy to derail

The University of Connecticut has a university professor named Christin Munsch. She has a male friend who is unemployed, mainly relying on her wife to earn money to support her family, but she found out that he was derailed by chance.
She can't figure out, her friend should be grateful to her wife, how can she be derailed? What kind of group has the highest probability of derailment?
This led to the curiosity of this professor, so she began a decade of research on this issue and did a lot of data investigation.
Later, she published her research results in the famous academic paper magazine "American Sociology Review", and her data caused people to be shocked.
In our consciousness, it should be that rich men are the most likely to derail, because they have money to find a junior, to support mistresses, TV is played like this.
However, Professor Christin Munsch’s conclusion is the opposite. The rich man is not the easiest to derail. The most easily derailed man is the man who eats soft rice.