Looking at my Endpoint Server in the System Overview, I see that my Endpoint Server has incidents, but there are no messages.  How can that be?

The Message count for an Endpoint Server is a count of the number of messages that were processed on the Server. 
This count only increments if there is a two-tier policy (EDM, IDM) that requires the message to be sent to the server. 
We do not keep track of the number of messages processed by the agents.

The Incidents count includes both the incidents reported by the Endpoint Server and the incidents reported by the agents connected to that server.