I've experienced 3 responses to negs:
1. Attraction
2. Lost attraction
3. (The most intresting one) They see me as "hard to get" and moves on to an easy AFC.
- So maybe you shouldn't neg so hard on easy/desperate girls!
But still negs are pure gold. Every AFC starts hitting on the girl right away by giving her compliments or start touching her in a uncomfortable way. By disqualifying her, she will start chasing you IF (and this is important) you have gained enough attraction and have delivered your negs in a C&F way!