The cost of inaction framework, explained with numbers
August 22, 2026 · 6 min read
By Kennon C. Bauman, founder of PropelQuote
Cost of inaction is the monthly loss a problem causes multiplied by the months it persists. A $4,000-a-month problem lasting twelve months carries a $48,000 cost of inaction, which justifies a fee of $4,800 to $9,600. It only holds if the client confirms the monthly figure and the horizon is realistic.
The calculation
Cost of inaction is monthly loss multiplied by the number of months the problem persists. A support backlog costing $4,000 a month over the twelve months before anyone fixes it carries a $48,000 cost of inaction.
The $48,000 cost-of-inaction estimate, based on a $4,000 monthly loss over twelve months, is your value anchor. A fee of $4,800 to $9,600 against that anchor is straightforward to justify, because the client is comparing your invoice to a loss they already accepted.
Where it overstates the case
Three cost-of-inaction modelling errors make finance teams dismiss the estimated client loss outright:
- Counting the same money twice — lost revenue and wasted staff time that already overlap.
- Assuming an unrealistic horizon. Twelve months only holds if nothing else would have fixed it.
- Using a monthly loss the client never confirmed. If you supplied the number, it is your number, not theirs.
Sanity-check against other frameworks
Cross-check cost of inaction against time-to-value compression (monthly upside multiplied by the months you save the client) and the expected value matrix (impact multiplied by the change in success probability). If cost of inaction is triple the other framework estimates, your horizon or your monthly figure is probably too aggressive.
When the frameworks disagree, showing a range is more credible than defending the highest number. PropelQuote lets you anchor on high, low, middle, or a range and shows the client only what you selected.
Say it out loud that it is an estimate
Every model rests on assumptions the client supplied. An explicit disclaimer that ROI figures are illustrative estimates, not guarantees or financial advice, costs you nothing in credibility and gains you a lot. PropelQuote includes one on proposals and live views by default; you can toggle it off, but there is rarely a reason to.
Key takeaways
- Cost of inaction = monthly loss x months unresolved.
- Never use a monthly figure the client did not confirm.
- Cross-check against time-to-value and expected value before anchoring.
- Keep the estimates disclaimer on.
Sources
- Kahneman & Tversky (1979), "Prospect Theory: An Analysis of Decision under Risk," Econometrica 47(2)The original study showing people weigh losses more heavily than equal gains — the reason a cost-of-inaction figure lands harder than an upside figure.
- Samuelson & Zeckhauser (1988), "Status Quo Bias in Decision Making," Journal of Risk and Uncertainty 1Experimental evidence that decision-makers stick with the current option, which is why the cost of doing nothing has to be made visible.