Learn About Your Non-Buyers,
by Herschell Gordon lewis
Too
many marketers spend all their research time and money learning who their
buyers are and why they act as they do. They should, instead, spend their
resources learning why non-buyers don't buy. The direct marketing universe
opens up dramatically once you understand who might be a buyer but hasn't
been (1) reached at all or (2) reached properly.
(Taken from Direct Marketing Strategies And Tactics.)