A direct line item under-delivers when it loses requests to other demand, when its targeting is too thin for its goal, or when pacing holds it back. Check pacing first, because it is the cheapest to read. Open the Troubleshoot tab, read delivery by day, and compare the goal, the end date and the targeting.
The advice below is for goal-based line items such as Standard. Sponsorship items are paced by a percentage of impressions rather than a goal, and Programmatic Guaranteed and Preferred Deals have their own rules, so check the pacing page for those types before you apply any of this.
What pacing does with a goal
When a line item starts, Ad Manager spreads its goal over the time left. It recalculates daily and hourly goals regularly, and straight away if you change the budget or the dates. With Evenly, the default, the item is paced across its start and end dates but can deliver up to 5% above goal as a safeguard against a shortfall. Frontloaded starts at up to 40% above goal and slides down to 5% ahead of schedule near the end.
Google's own example makes the numbers concrete: 10,000 impressions over ten days. On day one, Evenly aims at about 1,050 impressions and Frontloaded at about 1,400. Neither gives you a flat 1,000 a day, because delivery also follows the traffic shape of the inventory the item targets.
"As fast as possible" is a setting too, and it behaves differently. That line item is never considered on schedule. It takes every impression it can win, and Google warns it can end early if the goal is reached before the end date. There is also an unlisted version of it: in the last hour of a campaign, a line item that still owes impressions acts as if it were set to deliver as fast as possible.
What a late line item does when it catches up
Ad Manager tracks how far ahead or behind schedule each line item is. Google calls the measure the satisfaction index. A line item that is behind gets selected more often. The correction is gradual, and Google says it can take several hours to fully correct.
Two things follow from that, and both are in Google's pacing article.
First, aggressive catch-up is on by default. If a line item falls behind or is paused for a while, Ad Manager tries to recover the missed impressions during the next day in your account's time zone. For a paused item, the catch-up runs on the day it restarts. Google's example: a line item with 100,000 impressions over ten days delivers 10,000 a day for two days, is paused for four days and restarts on day seven. That day Ad Manager tries for about 50,000 impressions, 10,000 for each paused day plus 10,000 for the current one.
Second, a campaign that is behind "may even serve ahead of higher-priority campaigns" that have recently started delivering and are expected to deliver in full. So a late Standard item can serve ahead of a higher-priority item that has only just started delivering, and Google still expects that higher-priority item to reach its goal. Google's list of line item types gives Sponsorship priority 4 and Standard 6, 8 or 10, and says lower numbers rank higher, but it also calls type "only one factor in ad selection".
Google does not say where a catching-up item delivers, so treat this part as an inference, not as Google's documentation. A broadly targeted item, say run of site, has a lot of eligible traffic to draw on, so it may take the extra delivery wherever the volume is. Do not assume it went where you sold it: run the report by ad unit and look. Google does warn about a related case: low goals on large inventory can partly over-pace, and it suggests narrowing the targeting.
Where to look in Ad Manager
Go to Delivery, then Line items, select the item, and open the Troubleshoot tab. It has two sections that matter here.
Health history shows recent setting changes, past forecasts and delivery progress by day. The default window is the last 7 days, and you can go back up to 45. Look for the day delivery fell off and compare it with the change log in the same view.
Non-delivery causes is a pie chart of the main reasons the item did not win eligible ad requests, with an estimate of eligible requests and the creative render rate. The Time period to display menu switches the chart between the last 7 days and the last 24, 12, 6 or 3 hours. If the chart is missing, check the line item's status first: it may be in pre-delivery, paused or complete.
Google lists the reasons below on its troubleshooting page. The first column is paraphrased from that page, so the wording in your UI may differ, and the last column is a suggestion, not Google's.
| Reason (paraphrased) | What it means | What to try |
|---|---|---|
| Lost in competition to line items of higher priority | Something with a lower priority number won the request | Check the priority, and whether a competing item is itself over-pacing |
| Frequency cap reached, or user missing identifiers | The cap blocks repeat serving, or the user cannot be counted | Loosen the cap if the forecast says there is room |
| Line item CPM is below the floor in pricing rules | The floor beats the item's rate | Check the rule that applies to this inventory |
| Lost to First Look, or to remnant line items with higher CPMs | A competing path paid more | Review First Look pricing rules and remnant CPMs |
| Delivery rate reduced to better match expected pacing | Traffic shaping is holding it back on purpose | Read the on-schedule indicator before you change the goal |
| Line item is on or ahead of schedule | Impressions are going to other campaigns | Usually fine. Check the totals at the end date |
| Did not serve due to exclusion labels or same creative exclusion | A competitive exclusion blocked the match | Check protection rules and exclusion labels |
Google's advice for the inventory side is to run a forecast on the targeting. If the numbers show not enough eligible traffic, widen the targeting, relax the frequency caps or extend the run. If they show plenty, the problem is competition or pacing.
A check to run tomorrow
Take your five largest direct line items by booked impressions and spend ten minutes on each.
- Open the Troubleshoot tab and read Health history. Find the last day delivery changed and note what changed with it.
- Look at the delivery setting. A Frontloaded item with a large goal will run heavy early and quiet late. Even an Evenly item does not deliver a flat count each day.
- Check the targeting against the goal. A small goal on large inventory over-paces. A large goal on a narrow ad unit cannot deliver.
- Run a historical report for the item with Ad unit as a dimension. If a late item has put most of its volume on one cheap ad unit, check whether that ad unit is part of what the deal sold.
- Look for pauses in the last two weeks. Each one can set off a catch-up the next day.
Then change one thing, and leave it. Google's pacing article says changes to pacing can take up to 48 hours to apply to traffic, and that changing goals while catch-up runs cancels the catch-up for that day. Google's page does not say whether the 48 hours applies to a single line item edit, so give any edit a full day before you judge it. Several edits in one afternoon leave you with a report you cannot read.
When the answer is not pacing
If the troubleshooting chart shows the item losing to higher priority or to higher remnant CPMs, the pacing is working as designed and the item is outbid. If a forecast on the same targeting shows too few eligible impressions, no pacing setting will fix it: widen the targeting, relax the frequency caps or move the end date, as Google's page suggests.
Avoid switching the item to As fast as possible as a cure. Google says that item is never considered on schedule and can finish before its end date, which is rarely what a deal with a flight period wants.
What Optimon adds
Optimon's daily briefing is the morning email on what moved in your Google Ad Manager account and why, with the numbers attached.
FAQ
How do I know if a direct line item is behind schedule?
Open the line item, go to Delivery and then the Troubleshoot tab. Health history shows delivery progress by day against the goal, and Non-delivery causes shows why the item lost eligible ad requests. A line item that is behind schedule is picked more often by the delivery controller, so look there first.
Can a behind-schedule line item beat higher-priority line items?
Yes. Google's pacing article says a campaign that is behind schedule may even serve ahead of higher-priority campaigns that have recently started delivering and are expected to deliver in full. Google also calls line item type only one factor in ad selection.
Does changing the goal fix under-delivery right away?
No. Google's pacing article says changes to pacing can take up to 48 hours to apply to traffic, and that changing goals during catch-up cancels the catch-up for that day. It is not clear that the 48 hours covers a single line item edit, so make one change, wait a full day, and read the daily delivery before you touch it again.
