A "SEV" (severity) is a production failure or incident, usually indicted with a level value. For example, a SEV 0 would be a total system unavailability incide

A "SEV" (severity) is a production failure or incident, usually indicted with a level value. For example, a SEV 0 would be a total system unavailability incident, SEV 1 might be a major issue with parts of the system, SEV 3 is a less critical failure affecting a subset of users, etc. You'll typically have a postmortem meeting afterwards to discuss the incident, the root cause, lessons learned, and action items to prevent future occurrences, which is the meeting described in the article.