Fix: Performance Max Ad Strength below Excellent

A Performance Max asset group rated below "Good" Ad Strength is throttled by Google's cross-channel matching engine — it produces fewer auction-time combinations, gets a narrower placement mix across YouTube, Display, Discover, Gmail and Maps, and bleeds Ad Rank on the inventory where creative diversity is the primary ranking signal. The fix is mechanical: fill every asset slot to the recommended minimums, then diversify message angles until the badge clears to Excellent.

Why this matters

Performance Max blends asset parsing, URL crawl, audience signals, and combinatorial creative selection into a single auction-time matching model that runs across YouTube, Display, Search, Discover, Gmail, and Maps. The Ad Strength badge is Google's pre-serve quality predictor — it summarizes how many distinct ad combinations the campaign can produce from the asset pool you supplied, weighted by message diversity and keyword inclusion. Below "Good," PMax can still serve, but the matching engine has fewer combinations to test, leans harder on URL + landing-page semantics, and gets squeezed out of inventory where creative quality is a hard gate (YouTube in-stream is the canonical example — thin assets simply don't qualify for premium placements).

The Whitead rule fires HIGH on every ENABLED asset group with Ad Strength below "Good" because the cost is paid quietly across weeks: lower impression share on high-CPM placements, narrower mix concentration toward Search-like surfaces, slower learning-phase convergence when you ship new offers. Severity holds even when the campaign is profitable, because the fix is cheap (a 45-60 minute asset-fill session) and the upside compounds — Google's own optimization guidance explicitly recommends targeting "Excellent" or "Good" Ad Strength for the full inventory unlock [1].

The rule does not gate on conversion volume or learning-phase status, because Ad Strength is a pre-serve diagnostic — the badge degrades immediately when assets are thin, regardless of how much spend the campaign has accumulated. Composite checks for individual asset-type gaps (zero videos, fewer than 5 images, fewer than 15 headlines) are handled by the sibling rules pmax_asset_completeness and pmax_video_missing to keep remediation narratives single-purpose.

How to verify the issue

1. Open Campaigns → select the Performance Max campaign → Asset groups. For each ENABLED asset group, read the Ad strength column. Any badge below Good (i.e. "Poor" or "Average") confirms the finding.
2. Click View details → Edit asset group on a flagged group and count each asset type: short headlines (30 char), long headlines (90 char), descriptions, landscape images (1.91:1), square images (1:1), portrait images (4:5), logos, videos, and sitelinks. Match against the documented minimums in the table below.
3. Check the right-side Ad strength panel inside the editor — Google annotates which asset type is the binding constraint ("Add more headlines," "Add a video," "Add unique headlines"). Treat the topmost annotation as the highest-leverage fix.
4. Cross-check whether the campaign has any auto-generated videos. Open Asset library filtered to Video for the asset group — entries tagged "Auto-generated" are the slideshow videos Google synthesizes when no real video is supplied. They count toward the asset count but materially under-serve on YouTube in-stream.

Step 1 returning any badge below Good = the rule's primary trigger. Steps 2-4 determine which asset type to prioritize.

Documented asset minimums per asset group

How to fix it

Plan a 45-60 minute working session per asset group. The sequence matters: fill text first (cheap, instant Ad Strength lift), then images, then logos, then video last (highest production cost but biggest brand-quality unlock).

1. Fill text assets to the cap. Open Asset groups → asset group → Edit asset group → Headlines. Write 15 short headlines (30 char each) across at least five distinct message angles: pricing/offer, social proof, unique value, problem statement, urgency/scarcity. Add 5 long headlines (90 char) that expand on the strongest angles. Add 5 descriptions (90 char) covering benefit-led, feature-led, and CTA-led copy.

   # Bad — five paraphrases of one claim (low combinatorial diversity)
   "Save 30% on subscriptions"
   "Get 30% off subscriptions"
   "30% subscription discount"
   "Subscription savings: 30%"
   "Discount on subscriptions — 30%"
   
   # Good — five distinct angles (high combinatorial diversity)
   "Save 30% on annual plans"                       # pricing
   "Trusted by 12,000+ teams worldwide"             # social proof
   "Cancel anytime, no questions asked"             # unique value
   "Stop losing leads to slow follow-up"            # problem statement
   "Offer ends Sunday — start your trial today"     # urgency
   

2. Add image assets to the recommended mix. Edit asset group → Images → +. Upload 3 landscape (1.91:1, ≥1200×628 px), 3 square (1:1, ≥1200×1200 px), and 1 portrait (4:5, ≥960×1200 px). Use product photography on white plus lifestyle shots — Google's matching engine selects against placement context, so variety in background/composition expands which surfaces qualify.

3. Upload logo variants. Add at least 1 square logo (1:1, ≥1200×1200 px, transparent or solid background) and 1 landscape logo (4:1, ≥1200×300 px). Five logos total gives the matching engine room to swap between hero and footer placements.

4. Upload a real video — do not rely on the auto-generated slideshow. Videos → + → upload at least one video ≥10 seconds, preferably one each at 6 sec, 15 sec, and 30 sec to cover bumper, in-stream skippable, and longer storytelling placements. If you lack production-ready video, see the PMax video missing fix article for the minimum-viable-video playbook (phone-shot product spotlight with on-brand title cards beats auto-slideshow).

5. Add 5 sitelinks. Sitelinks → +. Use deep links to pricing, demo booking, customer stories, top-converting category, and a comparison/why-choose-us page. Sitelinks contribute to Ad Strength even though they primarily serve on Search and Discover surfaces.

6. Wait 7-14 days before judging impact. PMax re-equilibrates combination selection across a learning-style window even though the bidding strategy is unchanged — the badge updates near-instantly, but channel-mix shifts and CPA effects take a week or two to surface in reporting.

"We recommend that your ad strength be Excellent or Good. Include at least 20 text assets (15 headlines, 5 descriptions), at least 7 image assets (3 landscape, 3 square, and 1 portrait), and at least 1 video asset."
— Google Ads Help, Optimization tips for Performance Max campaign for all business types [1]

How to confirm the fix worked

Diagnostic checklist — run all five 10-14 days post-deploy

• Every ENABLED asset group shows Ad Strength: Good or Excellent in Campaigns → Asset groups.
• Each asset group has ≥15 headlines + ≥5 descriptions + ≥7 images + ≥1 uploaded video + ≥5 sitelinks when counted in Edit asset group.
• Auto-generated videos are no longer the only video in any asset group — at least one uploaded asset per group.
• Channel mix in Insights → Performance shows YouTube and Display impression share holding or rising versus the pre-change baseline (no regression from creative-quality gating).
• Cost per conversion holds within ±15% of the pre-change baseline with conversion volume stable or up — Ad Strength fixes should not spike CPA; if they do, the new assets are off-brand or off-offer and need editorial review.

If all five pass, re-run the audit — the pmax_ad_strength rule moves from failed → passed.

Common mistakes

• Paraphrase padding. Filling 15 headline slots with five different ways of saying the same thing satisfies the count but not the diversity dimension of Ad Strength. The badge scores combination variety, not slot occupancy.
• Single-asset-group monoculture. Copying the same headline/image set across every asset group defeats per-AG learning. Each asset group should represent a distinct offer or audience cluster with its own message stack.
• Treating auto-generated video as "done." Google fills the video slot with a slideshow when you omit one, which lets Ad Strength tick up — but the slideshow serves on YouTube in-stream and is the single biggest visible-brand-quality risk for established brands. Real video is non-optional for any brand that cares how it looks on YouTube.
• Skipping logos and sitelinks. Both contribute to Ad Strength even though merchants treat them as afterthoughts. Logos unlock branded placements; sitelinks lift Ad Strength on the Search-surface portion of PMax serving.
• Re-uploading the same image at three crops. The matching engine reads pixel data, not file name. Three crops of one product shot count as one image's worth of diversity; ship genuinely different compositions.

FAQ

How long until Ad Strength updates after adding assets?
The badge typically refreshes within minutes inside the asset group editor and within a few hours in the Campaigns → Asset groups column. Channel-mix and CPA effects take 7-14 days to surface — Google's matching engine re-equilibrates combinations across a learning-style window.

Does "Excellent" Ad Strength guarantee better performance?
No — it's a pre-serve diagnostic, not a performance prediction. Excellent unlocks the full inventory and combination space, but offer-market fit, audience signals, and conversion tracking determine whether that broader serving converts. Treat Ad Strength as a prerequisite, not a lever on its own.

What if my account has 15+ asset groups — do I have to fix them all?
Yes, but sequence by spend. Sort asset groups by 30-day cost descending and fix the top 80% of spend first; long-tail asset groups can wait a cycle. The rule fires on any ENABLED group below Good, so the audit will keep flagging tail groups until you reach them.

Can I skip the video slot if I'm a service business with no product to film?
No — the auto-generated slideshow will serve in your place, and it usually looks worse than amateur phone-shot footage. See PMax video missing for a minimum-viable-video approach (phone-shot testimonial, screen-recording with voiceover, or animated logo + on-brand title cards).

Does pinning headlines help Ad Strength?
No — pinning reduces combinatorial diversity and almost always lowers the badge. Pin only when legal/brand mandate requires it (e.g. brand name in headline 1 for a brand defense campaign). Otherwise leave headlines unpinned.

Sources

1. Google Ads Help — Optimization tips for Performance Max campaign for all business types. https://support.google.com/google-ads/answer/11385582 (accessed 2026-05-26)
2. Google Ads Help — About Performance Max campaigns. https://support.google.com/google-ads/answer/10724817 (accessed 2026-05-26)