Vernon Schyrver in news.admin.net-abuse.email:

The trouble with all "Good Guys" lists is in who pays. Maintaining a comprehensive list that can be widely used is expensive. [...]

Sooner instead of later, those who have financial reasons for seeing themselves certified as good assume the financial burdens and so are given control. Organizations whose mail is never blocked can't find a reason to pay third parties for testamonials. They tell their correspodents "If you want my mail, orders or whatever, whitelist me or otherwise arrange to hear from me, but if not, that's ok too." That leaves organizations that for various reasons don't inspire enough trust on their own to pay for and so run the "Good Guys" list.

(From Message-ID <eittga$26l6$1@calcite.rhyolite.com>.)