Lists Scale

A defined audience beats a large one.

The first deliverable is a count, not a file. Records are reconciled across sources before anything is counted. Lineage survives the handover rather than being stripped at the door.

Count reconciliation after build

Re-running the figure against the finished extract, so the two cannot drift apart unnoticed.

Whitespace discipline

Removing the invisible differences that make two identical values compare as different.

Rejection reasons

Every discarded row carries the rule that discarded it, in plain words.

The counts cost nothing. What they imply is the part worth discussing.