What Are Slow, Gradual Declines In Google Referrals?

What Are Slow, Gradual Declines In Google Referrals?
I see a lot of different web sites, with a lot of different problems. From manual actions, to huge drops after a major algorithm update, to hacked sites, to sites that block Google by accident. The ones that always make me wonder are the ones that aren't hit hard one night but rather see a slow but consistent decline in organic traffic from Google.

I am sure you have seen them yourself and I see thread in the Google Webmaster Help forums on this topic all the time.

Author: Barry Schwartz