Log Only What's Needed

Ensure that anything the application logs is either at the right log level or has a useful purpose.

Rationale

If left unchecked logging can be become an unmanageable stream of events that distract away from the operability of the application.

The most common culprit is events logged that were used during development for debugging, this is usual a smell that there is a test missing for a scenario. Consider writing a test rather than a debug log.