Why a Valuation Decays
The moment you finish a valuation, it begins to age. Not because the work was wrong, but because the world it described keeps moving. Price ticks every second. The company reports fresh numbers each quarter. And time itself pulls the future you discounted a little closer. A fair value is a photograph, not a monument.
Three clocks running against your estimate
Every saved valuation is quietly undermined by three things moving at once:
- Price drifts continuously, so the gap between price and your fair value — the entire reason you cared — is never the number you last saw.
- Fundamentals update in steps: earnings, growth, margins, and guidance all revise the inputs your estimate was built on.
- Time advances, so cash flows you once discounted over five years are now four, and the terminal value sits closer.
A valuation is a snapshot of inputs at one moment. Leave it untouched and it does not stay accurate — it silently drifts into a number that no longer means what you think it means.
- Valuation decay — the gradual loss of accuracy in a saved estimate as price, fundamentals, and time move on without it.
- Snapshot estimate — a fair value that is true for the inputs and moment it was computed, and no longer.
- Maintenance — the deliberate act of refreshing an estimate so it keeps describing reality.
A worked example
In January you value a business at $120 while it trades at $90 — a compelling 25% discount to your estimate. You save the analysis and move on.
By July the stock is $110, the company has posted two quarters of slower growth, and six months of the forecast horizon have elapsed. Your saved file still says "$120 fair value, 25% discount." But nothing about that sentence is still true: the price is different, the growth input is stale, and the horizon has shrunk. Acting on the January file in July is acting on a photograph of a room you have already left.
The tool keeps the picture current — you keep the judgment
This is exactly what ClearGuidance is built to carry. Your saved valuationThe live fair value that updates as you move the assumption sliders. and its baselineThe baseline fair value shown before you adjust any sliders. are not meant to be filed away and forgotten; they are meant to be revisited, so the comparison between price and value stays honest. The rest of this course is about the machinery that does that revisiting for you — baselines, alerts, staleness controls, and one-click re-valuation.
None of this tells you what to buy or sell. The terminal keeps your estimate current and prompts you to look; the decision is always yours to make.
- Open a stock you looked at weeks ago in the terminal.
- Compare today price and inputs to what you remember concluding then.
- Notice how much the price-to-value gap has shifted without you doing anything. That shift is decay — and the reason maintenance matters.
- A valuation is a snapshot, accurate only for the inputs and moment it was made
- Price, fundamentals, and time all move against a saved estimate
- An unmaintained valuation drifts into a misleading number
- The terminal exists to keep the estimate current; you supply the judgment
In the next lesson we look at the number the terminal shows you before you touch anything: the market-implied baseline, and what it honestly does and does not tell you.