The Three-Case Model

Plan a range, not a number. A 10 to 15 percent variance band turns a shortfall into an update instead of a surprise.

Forecast model with three cases, worst, realistic and best, where the realistic case is the plan, inside a 10 to 15 percent variance band

How do I build a revenue forecast with best, realistic and worst cases?

The Three-Case Model replaces a single forecast number with a range: a worst case, a realistic case and a best case, inside a 10 to 15 percent variance band. The realistic case is the plan, the number every leading indicator ties back to. The band turns a shortfall into an update the board has already seen, not a surprise.

Run the business against the range every week, and a shortfall shows up as a trend line long before it shows up in a board deck. That gives you time to act on it. A board that has already seen the worst case in writing doesn’t treat a miss as a betrayal.

How to use it

Build the realistic case first.
This is the plan: the number the business is actually run around. Tie every leading indicator to this line, not to the best case.
Set the worst case.
The number the board can absorb without a strategy change, 10 to 15 percent below the plan.
Set the best case.
What the plan produces if every assumption holds, 10 to 15 percent above. Never the number a board should expect by default.
Track the band every week.
Compare actual and projected results to all three cases as the quarter unfolds, not after it closes. A trend toward the worst case is the signal to build a Bridge Plan.
Put all three cases in front of the board in writing.
Name the realistic case as the plan, so a result inside the band reads as an update.

Questions

What variance band should a revenue forecast use?

A 10 to 15 percent band on either side of the realistic case.

What happens if results fall below the worst case?

That is a miss, not a variance. Diagnose it with the Miss Diagnostic before deciding what to do, then build a Bridge Plan back to budget.

The Three-Case Model is an Uphoff Advisory Framework created by Tony Uphoff, five-time B2B CEO and founder of Uphoff Advisory, first published in Uphoff on Media on September 8, 2026. Read the full piece: The Miss Isn’t the Failure. What You Do Next Is