Pretty girls have it harder? Watch
The point is that they will attract the wrong people for long lasting relationships and have to weed out these people to find someone right for them - some douchebags act differently around women anyway, as they win them over before resorting back to their douche ways once they get comfy. Younger girls often have more trouble realizing that the guy after them is a douche, once girls mature they get rid of these people.
I once had this discussion with an older male friend as I was seeing a guy and wasn't sure if he was serious about me. He did constant initiatives, became jealous, invited me on holiday, made me a priority etc. I asked my friend how much effort he could be making for sex alone, and he said " a lot". He said I may be the most attractive girl this guy has been with, and therefore he'd be willing to put in a lot even if he didn't want to be my boyfriend.
As you get more experienced (and cynical) a woman will get better at filtering out the losers/*******s, but there is no foolproof way of doing it. Intelligent women in their 40s are still victim of abusing husbands even if they had a thorough selection process. Some guys just give amazing acting performances and that's the way of life. So yes, this bit is more difficult for attractive women, even though every woman needs to work hard at spotting the red flags.