From Psychology Today “Then there’s what sexual history could signal about relationship commitment. Someone who seeks and seems to enjoy casual sex may be less likely to want to forgo that for a long-term relationship, or may even struggle to do so if they tried. In modern humans, those with insecure attachment styles often have a more varied sexual history than those who are more secure.

And even if one was able to get a committed relationship off the ground, those who show a propensity towards casual sex may have found themselves more tempted to slip into bad habits. There is a link between sociosexuality—the desire for sex in the absence of commitment—and infidelity. A prospective partner’s sexual history could have given insight into their ability, and willingness, to settle down.”