The Social Pathologist had a good post awhile back about a study showing divorce risk by partner count.
As it shows, successful marriages are much more likely for a woman with a low partner count. But a better way to look at it is how many men fail to successfully keep their wife. Which can be turned around to how many men you need better relationship game than to keep your wife.
So, for a women with 0 partners, you have to have better relationship game than ~20% of men, but to successfully keep a woman with 16-20 partners, you have to have better relationship game than ~82% of men. This is why her notch count is important, because it’s always just a fifth of men that are in the top quintile.
*The Chateau also covered this topic.