Noticed the other day that the referral traffic from a very well known web directory (clue: yellow) to my clients had slowed down to nothing.
Checked with client that they hadn’t decided to stop using the services. This uncovered the fact that although the renewal for a premium spot had been renewed the service provider hadn’t put it live.
Result an immediate refund, lots of apologies and, more importantly, the channel back up and running.
So keep checking the stats to see if referrers or keywords or campaigns are still delivering what they should or what you expect.