This one is useful when the two parties are equals, but it is horribly wrong in negotiating with a future employer.
Once they've identified you as someone they want, and they've made you an initial offer, nothing you can say* will make them walk. And if you negotiate well, you'll be identified as higher value than someone who didn't.
*Within reason - if they offer $120k and you ask $150k, that's fine. If they offer $120k and you ask $500k, you might run into problems.