Part of Hints for Operating High Quality Services by
Very Very Early Draft 0.1 -- January 30, 2004
You need to have metrics, track those metrics, and have processes in place to improve the metrics you are tracking. Periodically you need to re-examine your metrics to determine if they are measuring what you think they are measuring, and to determine if they are still useful metrics to track.
Managing a Production Service, Geoff Halprin, White Page, SysAdm Group