Forecasting you can defend in the S&OP room
A forecast is only useful if the room believes it. That means you need to explain how it was made, not just what it says.
Updated June 2026 · iForecastPlan team
Black-box accuracy does not survive contact with a sceptical sales director. The moment someone asks why an item is forecast to jump, a model you cannot explain loses the argument. Defensible forecasting is about method you can show, not just a number you produce.
Route each item to the right model
Fast movers and lumpy spares do not behave the same way, so they should not share a model. We classify each item by how intermittent and how variable its demand is, then route it to a model suited to that pattern. A steady runner gets a different treatment from a part that sells twice a quarter.
Prove it with honest validation
We hold out recent periods and test the model as if it had never seen them, using an expanding window so the test mirrors how you actually plan. Outliers are corrected before they distort the fit, and the correction is visible. Nothing is hidden in a coefficient.
Grade the data before you trust the forecast. A confident number on poor history is worse than an honest wide range.
Grade the inputs
Every item carries a data-quality grade, so planners know which forecasts to trust and which to review. Seasonality for festivals, weather and end-of-quarter pushes is modelled openly, so a spike in the plan has a reason you can point to.
Accuracy wins deals with statisticians. Transparency wins the S&OP room. iForecastPlan is built so you can show your working every time.