Hard case

A quality finding where the classification is genuinely ambiguous because a business rule, legal requirement, or intentional design choice might explain the pattern, requiring lineage tracing or direct confirmation from the data's owning team before a fix is committed, rather than a mechanical application of the six-failure-mode test.

One of five recurring, real-world scheduling situations, part-time hours, an externally gated technical block, multiple concurrent builds, a passed docking window, or cohort pacing, identified in this topic (Section 3H) as requiring a specific adjustment to the standard interleaving guidance rather than abandonment of the principle.

A request in which the underlying rail or pattern is correctly identifiable but does not, on its own, resolve whether the specific instance is legitimate or fraudulent, requiring the rail check to be paired with independent verification rather than used alone, as catalogued in Section 3G.