Referrals

I see some people requesting referrals over here who are often ignored, and I'm surprised because Blind for me seems a much better community to ask for referrals as a deserving engineer than knocking random LinkedIn users. People of Blind, what do you want in a person so that you are willing to refer him/her into your company? P.S. you get a good referral bonus, so you have incentive enough to refer, that's what puzzles me