decision drift
decision drift: The gradual change in the real reason for holding an asset without a documented update to the thesis.
Plain-English Explanation
Decision drift happens when the position is still in the portfolio, but the original logic has quietly changed or weakened without being recorded. The story in the team's head moves, but the written thesis does not.
Why It Matters
Undocumented thesis changes make review quality worse because nobody can tell whether the position is still being held for the original reason, for a revised reason, or simply by inertia. Catching drift early improves accountability and makes exits or re-underwrites more deliberate.
Next Step
Compare the current reason for holding a position with the last written thesis, then document any change before the next review cycle.
Examples
- A stock was bought for margin expansion, but months later the team is defending it on valuation alone. Writing that change down exposes whether the position still fits the original case.