Assumption logs that people actually update
If an assumption log feels like paperwork, it will die in week three. Design it like a working instrument instead.
Keep each entry short: claim, owner, evidence link, invalidation trigger, last reviewed date. Anything longer becomes a wiki nobody opens. In Forecast Decision Lab Module 2 we practice writing entries in under ninety seconds so the habit can survive a chaotic Monday.
Put the log where the decision lives
Do not bury assumptions in a separate knowledge base. Attach them to the decision brief or the forecast notebook. Proximity beats perfection for business analytics workflows that move weekly.
Review on a timer, not on instinct
Instinctive reviews happen only after something breaks. Schedule a fifteen-minute assumption audit each month. Archive stale claims rather than letting them accumulate guilt. A short living list beats a long abandoned one.
Teams that maintain assumption logs make fewer silent errors — not because they predict better, but because they notice when the world changed sooner.