When matching tolerances quietly widen

Matching tolerances exist so minor price or quantity differences do not stall every invoice. Over time, someone widens a percentage “just for this supplier,” then forgets to narrow it again. Inside many invoice processing applications, that history is buried in configuration screens operators never open.

During an application audit we ask for the current tolerance table and compare it with a sample of matched invoices from the last quarter. Patterns appear quickly: one commodity category with a five-percent blanket; a temporary exception that became permanent after a busy fiscal close.

The fix is rarely dramatic. Controllers restore tighter defaults for routine purchases and keep wider bands only where contracts truly vary. Documenting why a tolerance exists matters as much as the number itself — the next administrator will inherit the setting without the story.