> Pick a server or a piece of enterprise software and go take a look at its logs. If it's doing anything interesting at all, it'll be full of errors.
It's true, but IME those "errors" are mostly worth ignoring. Developers, in general, are really bad at logging, and so most logs are full of useless noise. Doubly so for most "enterprise software".
The trouble is context. Eg: "malformed email address" is indeed an error that prevents the email process from sending a message, so it's common that someone will put in a log.Error() call for that. In many cases though, that's just a user problem. The system operator isn't going to and in fact can't address it. "Email server unreachable" on the other hand is definitely an error the operator should care about.
I still haven't actually done it yet, but someday I want to rename that call to log.PageEntireDevTeamAt3AM() and see what happens to log quality..