This is about our good ol’ hormone, testosterone. If you don’t already know this, testosterone is implicated in most attributes that we describe as ‘masculine’. Higher testosterone is correlated with assertive behavior, greater muscle mass, risk-taking, leadership, higher sex drive, squarer jawlines, abdominal musculature due to low fat, and aggression (with a caveat). The caveat on aggression is that low testosterone is associated with bullying behaviour, but high testosterone is associated with aggressive behaviour in the face of perceived injustice.

Virtually everything that women find attractive in men, both in appearance and behavior, are related to testosterone.

Testosterone levels automatically rise in anticipation of a challenge. After the challenge testosterone rises again if you succeed and falls if you fail.

Women are attracted to winners, because winners have higher testosterone levels. One way for someone to quickly increase their testosterone levels is to succeed in a challenge.

Like, say, a shit test.

When a woman shit tests a man she is offering a challenge, the outcome of which will determine his testosterone levels. If he passes, they rise, along with her attraction. If he fails, they fall, along with her attraction.

This is also why high testosterone men get fewer shit tests: their testosterone levels are already apparent and women instinctively discern this.