Out-of-stock products in Shopping: fix the feed or let the campaign absorb it?

Picture a store with about 3,000 SKUs where roughly 8% are sold out on any given day because of supplier delays. The feed often keeps showing them as in stock for hours after they sell out, so the campaign pays for clicks that land on dead product pages.

My view is that the feed should be the source of truth. Sync availability at least every few hours and mark items out of stock as soon as the inventory system knows. Google handles some of this on its own, but the lag is where the wasted spend comes from. A custom label for sold-out items also lets you keep campaign structure stable instead of pausing product groups by hand.

The counterargument is that restocks often come back fast and rebuilding learning is costly. Fair, but for items that stay gone for a week or more, I'd rather lose a few days of impressions than pay for clicks that can't convert. Where do you draw the line, a fixed number of days or something tied to sell-through?

I don't think the lag is where most of the wasted spend comes from. A few hours of stale availability is annoying, but the bigger leak is products that sit in the feed as "in stock" for days because nobody set a rule for what happens when the count hits zero. Say a store has 240 sold-out SKUs on a given day. Syncing every three hours trims a few clicks per item. Leaving backorders on, or letting the page show "notify me" while the feed says available, keeps paying for clicks that bounce. That's a policy problem, not a sync frequency problem. Before tuning the interval, pull how many sold-out SKUs have been live for more than 48 hours. If that number is high, the rules are the issue. If it's small, Priya's lag argument holds.

The 48-hour pull has a catch: check availability at the variant level, not just the parent. If your feed groups sizes or colours under one item_group_id, the product can read as in stock because a single variant still has units, while the sold-out size keeps collecting clicks and sends people to a page that says unavailable. Merchant Center accepts availability per variant ID, but a lot of feed plugins only push it at the parent. That means a SKU can look healthy in your count and still be the one bleeding spend.

Honestly I'm not sure a sold-out size keeps pulling clicks in Shopping. Each variant is its own offer with its own availability, so once Merchant Center marks that ID out of stock it generally stops serving. The leak I'd look at is the link. If every size points to the parent URL and the page opens on a default size that's sold out, the click is wasted even though the ad was valid. Comparing the landing URLs against the variant that's actually out will show you that faster than counting parents.

Agreed the landing URL is where it leaks. A sold-out default size also drags down the sizes that are in stock, since shoppers bounce before they ever find one. Setting the default to the first available variant is a quick fix. Does your feed send availability per variant ID, or only at the parent level?

Setting a default size only helps if each variant has its own URL. If you've got one parent page with a JavaScript size picker, the crawler and the feed still see a single landing page, so a click can still land on a sold-out default. Does your store give each size its own URL, or is it one shared page with a picker?

If all the sizes share one URL, the feed can't fix the click by itself. My rule of thumb is that the page should always open on a size that's actually in stock, and the product only stays in the campaign while at least one size can ship. You pay for clicks on a URL, not on a size, so if the page lands on a sold-out size the shopper bounces before feed availability even matters.