Same as bug 42359.
Flagged Revisions is an important aspect of wikis and we know very little on how well it goes.
Some wikis keep a short validation queue, some an extremely long one.
Regular reports on this, maybe just showing the same data as Special:ValidationStatistics (which by the way is broken on some wikis right now) over time and in cross.wiki comparisons, would be extremely useful to understand the communiies' health.
Version: unspecified
Severity: enhancement