All girls have that "one hung ex"

I am about 20-21cm (7.5-8inches) and quite girthy. Yet, so many girls I've been with have had a bigger ex boyfriend (I have a bad habit of asking). How is this statistically possible? I'm in the top 10% at least of all men. The chances of girls having a bigger ex should be extremely low if a girl has had less than 10 partners. Is it just skewed by memory? Maybe girls exaggerate their memories of someone over the years?