A payment lands
$1,200 short. Watch.
The reason is in somebody's inbox
The drift monitor flags the gap. The agent checks the contract, the CRM, then finds the CEO's discount email nobody told finance about. Revenue, forecast, billing and audit all move together, to the same cent.
Nothing posts without proof
Every entry carries a workpaper: the math, the exact quoted evidence, the approval. Deterministic code re-performs every check. Change one letter of the quote and it is rejected.