In some quarters, this is referred to as a go below.
Men, in general, like women, do cheat, but when a man, given his sexual conquests, goes for a far less attractive woman than his common average, then spouses are bound to question.
This phenomenon is as common as it is puzzling.
Most women tend not to have the ability to comprehend their partners' choice of a cheating partner.
This fact, for instance, could lay a road map to the inner workings of the women in question. Questioning the outward appearance, other than the act of infidelity itself could illustrate the level of self-absorption and lack of maturity on the display.
However, several factors come into play when seeking out these answers.
Stating the obvious, looks aren't everything. As much as women work on their outward appearance, an ugly personality might just drive your man crazy and into another woman's arms in spite of her looks.
Another reason could be totally psychological, most men tend to view less attractive women as having an overcompensatory tendency of offering love and affection to counteract the shortcomings of their physical appearance.
While writing this journal, Jim McNulty, an author of the Journal of Personality and Social Psychology, attests to the fact that infidelity was negatively related to own attractiveness amongst women. Therefore unattractive women are far more susceptible to cheating as opposed to attractive women.
Ultimately, nobody chooses who they fall in love with.
This applies to men too, provided a woman is kind, loving and attentive, a man is inclined to fall for her charms.
As you ponder, know that beauty lies in the eyes of the beholder.