These girls are ego whores, and will suck the life out of any guy that comes up to entertain them, make the guy feel like crap while feeding their own ego. They will say things like "I'm so fat", and wait for the guy to pour compliments all of them. That's the "self esteem" issues Neil is talking about.
She wanted "personality" aka beta cuck entertainment for the evening that she could then reject and get her daily ego boost. These girls typically have several beta guys orbiting them, to constantly feed the girls ego, and the guys get nothing in return... just used.
They will sleep with the occasional ultra chad (1 in 10,000), but that's not what's being discussed here,
Neil Strauss wants guys to keep throwing themselves onto the alter of rejection, and then to go buy his shitty books when it doesn't work out, for shitty advice. That's how he makes most of his money. That's why he says it's all about personality, and writes shitty articles like this.
Oh btw, if you want to know how much 10/10 sluts get approach just search "Street Harassment" into youtube; you will see hotter girls get approach just as much as juggernauts, if not more, and in a city it's pretty much at least daily.