Based on these stats, practice makes perfect. 10 more hookups and they're there. These stats make you wonder why any female has sex more than once. If at first you don't succeed, try, try again, I guess. Cosmo said so. More likely, poor study. For one thing odds aren't the same thing as probability which the write up appears to confuse.
I cum with most at least one. Whether they cause it all the time is something else ie. stimulating myself with my hand or a vibrator depending on the position etc.