Look at the conditions.
Software behaviour depends on its version, settings and the information it handles. A problem found in an older release may have been fixed. Another may only appear with a particular account or configuration.
The review checks those conditions before drawing a conclusion about the system in front of it.
Test in a controlled environment.
Recreating a suspected failure can help explain its cause without exposing a live system to unnecessary disruption.
The useful result is a clear account of when the issue applies, what it affects and what change would address it.
About this note
This note explains a review principle. It makes no claim about a particular live system.
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