I've found that the difference between a good neg and a hurtful neg depends on one thing: the seriousness of the thing you're negging (for both of you).
Example of bad neg. Talking with a girl that was kind of lower-class type, not really sparking my interest. I made fun of her style, implying she was a feminine tomboy, because she dressed kind of dumb skater style, not classy at all. But the truth was, her style really was stupid to me, I genuinely didnt like it. So even though I brought this across in a playful way, I must have subcommunicated that I meant it. She kept saying: "I never know if you're serious or not." The problem is, I was really half-serious. Don't neg her on stuff that you actually mean as criticism. Don't neg sincerely, in other words.
Good neg. I was chatting up a girl in a class I had to assistant teach. She had highlighted an entire page of her notebook. We were getting along really well, high IOIs, she was laughing and into me. I said, "Look, you highlighted the entire page, what good is that? You probably didn't even read it. But the important thing is, now it looks like you did." She replied "Exactly." and then we both laughed. That raised her temperature noticeably and got us both laughing together.
so negs backfire when you are negging on something that you genuinely are not cool with, and with low-selfesteem chicks.
