What it means
A supplier promises a morning delivery for a production line. Goods arrive the previous evening when the dock is closed, or the next afternoon after the line needs them.
A simple "delivered this week" report hides both misses. Define the window from the purchase order or confirmed supplier schedule, since a broad internal forecast is not necessarily the supplier's commitment.
Oracle's supplier delivery-performance guidance compares receipt date with promised date and allows a configured number of early or late days, so a business should state its own tolerance and keep the original promise visible. ASCM discusses on-time supply and supplier delivery as reliability measures, and a precise window can be more useful where docks, crews or production steps need timed arrivals.
An illustrative adherence rate is eligible receipts recorded within their agreed windows divided by all eligible receipts with known arrival outcomes, so if 180 of 200 qualify, adherence is 90%. Decide whether to measure purchase orders, shipments, lines or units, because one order split into two trucks may be partly on time and the chosen unit changes the rate.
Record actual arrival, not merely carrier dispatch, since a supplier can ship on time and still miss the receiving appointment. Keep requested, promised and revised dates separate: a buyer-requested change can create a valid new plan, but it should not quietly replace a missed original commitment in historical reports.
Treat early as a potential exception, because unplanned early stock can occupy scarce dock or refrigerated space even if late delivery is usually worse, and check receiving hours and holidays, since a Friday-night arrival at a closed dock may effectively be Monday receipt. Validate proof, as gate scan, signed delivery note and system posting can occur at different times, and a supplier's timing should not be judged solely by a warehouse clerk's later posting.
Review partial quantity, because a small pallet arriving on time does not mean the entire promised order was met, so pair window adherence with quantity completeness. Segment by supplier, item and route, since one congested port or carrier can explain a pattern across several suppliers while one vendor may repeatedly miss a specific line, and track reason and consequence, as production delay, rush transport, extra storage or customer delivery risk can make a miss material and a one-hour delay is not always equal to a one-day delay.
Avoid blame from timing alone, because an incorrect buyer address or changed appointment may cause a supplier to miss an apparent target. Use evidence for corrective plans, since a repeated missed morning window could call for an earlier dispatch, a different carrier or a revised realistic slot, and check capacity before changing commitments, because a supplier may offer a narrow window that it cannot consistently meet at peak load.
Keep cancelled orders out under a stated rule, compare mature periods only so that receipts scheduled for next week stay out of the denominator, and preserve receipts without a confirmed supplier promise as a separate data-quality group, since assigning them the buyer-requested date would turn an unconfirmed expectation into a supplier failure. For an owner, window adherence shows whether supply arrives when operations can use it, and it works best beside quantity and quality, not as a standalone supplier verdict.
In practice
Real-world examples.
Example
One hundred eighty of 200 eligible receipts arrive in their agreed windows, or 90%. The buyer reports the rate with the unit counted, the tolerance used and the period covered. The 20 misses are listed by supplier and route.
Example
A premature delivery to a closed dock is recorded as an early exception. The driver waits outside until the next morning, and the carrier charges waiting time. The buyer reviews whether the appointment was communicated to the supplier correctly.
Example
A partial on-time pallet is assessed separately from missing quantity. The window result is recorded as met for the pallet received. The shortfall goes to the delivery shortfall process so the order is not reported as complete.
Formula
Calculation
Illustrative window adherence = receipts within agreed arrival windows / eligible receipts with known outcomes x 100. 180 / 200 = 90%.
Breakdown with invented figures: of the 200 eligible receipts, 180 arrived within the window, 12 arrived late and 8 arrived early. Check: 180 + 12 + 8 = 200. Late share = 12 / 200 x 100 = 6% and early share = 8 / 200 x 100 = 4%, so the 10% of misses is split into two different problems.
The late arrivals may call for earlier dispatch, while the early ones may call for better dock scheduling or a firmer window, so the single 90% figure is only the starting point for diagnosis.Case study
Seen in the real world.
In this entirely fictional example, Elm Parts sees repeated afternoon arrivals against morning supplier appointments. It checks gate timestamps and buyer schedule changes, then agrees a feasible revised route. It retains the original missed-window history while testing later performance. Elm also found that a few apparent misses came from its own last-minute appointment changes. It marked those as buyer-requested revisions, kept the original commitments visible, and reviewed the next quarter's rate with the supplier using the gate scans as the shared source of truth.
Watch out
Common mistakes.
- Using warehouse posting time as the arrival timestamp without checking gate evidence.
- Marking a partial shipment fully compliant because one pallet arrived on time.
- Quietly replacing the original promise with a revised date in the historical rate.
Questions
People also ask.
Can early delivery be a miss?
Yes, if the agreed receiving window has an early boundary.
Is this the same as lead time?
No. It tests arrival against a promised window.
How are changed dates handled?
Preserve the original and approved revision under a clear reporting rule.
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