Illustrative data: 20,000 eligible users at two impressions each support at most 40,000 impressions in the cap period, before other losses.
It is easy to confuse matched inventory with eligible inventory. Forecasting can show plenty of matched requests while a strict frequency cap, a narrow audience rule, or a missing creative size removes most of them before the line item can serve. The campaign then paces behind even though supply looks fine.
A frequency cap is the classic example: a one-impression-per-user-per-week cap can filter the large majority of matched requests, and no amount of extra priority brings those users back. The delivery log usually makes this visible, showing a high matched count but a much lower eligible count with the difference attributed to the cap.
To fix it, separate matched from eligible in the delivery data, confirm the contracted frequency and creative requirements, then correct the cap period or creative association and reforecast the delivery that is actually reachable in the remaining flight.
Check the cap against the booked requirement
- Confirm the cap quantity, period, scope, and any overlapping caps.
- Inspect whether the affected requests are excluded by frequency or another rule.
- Compare the reachable audience with the impression goal.
- Verify creative sizes, targeting, and competing line items in the same segment.
Estimate the reachable delivery
A simple cap calculation is an upper-bound planning exercise. It does not account for uneven user visits, identity availability, other targeting rules, or auction losses.
Recover delivery within the agreement
Correct an incorrectly configured cap. If the configured cap matches the agreement, propose additional reach, a longer flight, or an agreed goal change. Do not loosen contracted limits just to improve the pacing chart.
Reforecast the remaining flight after the approved correction and monitor both delivery and frequency.
Test your reasoning: Separate reach from requests
Original simulated exercise. This is not a real client case.
A campaign has many repeat visits but limited eligible users.
Evidence available
- 10,000 eligible users in the cap period.
- At most two impressions per user in that period.
- Goal: 50,000 impressions in the same period.
Can these users alone support the goal?
Read the answer and next check
The simple upper bound is 20,000 impressions before other exclusions or losses. The 50,000 goal requires additional reach or an agreed change.
Next check: Confirm actual exclusion evidence and the contracted cap before proposing recovery.