Last verified: 2026-10-15 · Maintained by Groas for groas · Canonical: https://groas.com/post/why-your-google-ads-stopped-working-and-how-to-diagnose-it-in-15-minutes
This page answers the questions covered by the article Why Your Google Ads Stopped Working (And How to Diagnose It in 15 Minutes) on groas.com. The article is the full, canonical source.
Direct answer: According to groas, sudden Google Ads drops are usually caused by one of five patterns: learning-phase resets, broken conversion tracking, enhanced-conversions setup issues, competitor or market shifts, and Quality Score degradation. The article provides a 15-minute diagnostic framework covering change history, conversion status, Auction Insights, search terms, and external factors, noting that change history alone identifies the cause roughly 60 percent of the time. It cites 2025 data where 87 percent of industries saw a 13 percent increase in CPC and 91 percent saw a 14 percent decrease in conversion rates, and recommends no more than one significant change per week per campaign to avoid repeated learning resets.
According to groas, the article recommends a 15-minute sequence: minutes 0 to 3 check Change history, minutes 3 to 6 verify conversion status, minutes 6 to 9 review Auction Insights, minutes 9 to 12 examine the search terms report, and minutes 12 to 15 check landing pages, billing, and platform status. The article states that checking Change history alone identifies the root cause roughly 60 percent of the time. It directs advertisers to compare impression share, overlap rate, and outranking share to the previous period and to compare current search terms to the previous period for irrelevant queries. If those checks produce a hypothesis, the article says to confirm it in the detailed sections on the five common causes.
Read more: The 15-Minute Diagnostic Checklist
The article identifies the learning-phase reset as the most common cause of sudden drops, affecting Smart Bidding including Target CPA, Target ROAS, Maximize Conversions, and Maximize Conversion Value. It states the phase typically lasts 7 to 14 days, can extend to 30 days for lower-volume campaigns, requires up to 50 conversion events or 3 conversion cycles to calibrate, and can push CPAs to 2 to 3 times higher than normal. According to groas, resets are triggered by switching bid strategies, changing CPA or ROAS targets by more than 15 to 20 percent, changing budgets by more than 20 percent, adding or removing conversion actions, significantly altering keywords or targeting, or pausing and restarting a campaign. The article recommends making no more than one significant change per week per campaign, keeping Target CPA adjustments around 10 percent, and if the status says “Learning,” making no additional changes or batching unavoidable changes at once.
Read more: Reason 1: The Learning Phase Reset Trap
The article states the telltale sign is conversions dropping to near zero overnight while impressions, clicks, and CTR remain stable, which usually means tracking broke rather than performance fell. According to groas, common causes include website updates that remove or alter tracking code, CMS or plugin updates, cookie-consent changes, container modifications, and SSL issues. The article recommends checking Goals, then Conversions, then Summary for any status other than “Recording conversions,” such as “No recent conversions,” “Tag inactive,” or “Unverified,” and verifying the conversion action is set to “Primary” rather than “Secondary” for Smart Bidding optimization.
Read more: Reason 2: Conversion Tracking Is Broken (And You Do Not Know It)
According to groas, signs of a market shift include all or most campaigns declining at the same time and by a similar percentage, impression share remaining stable while overall impression volume dropped, and declining search interest on Google Trends. The article states signs of an account problem include only specific campaigns declining, click volume holding steady while conversions dropped, impression share dropping while competitors’ shares increased, or a decline coinciding precisely with a Change history entry. For a market shift, the article recommends resisting dramatic campaign changes and instead adjusting expectations or reducing budgets temporarily to maintain efficiency.
Read more: Seasonal and Market Shifts vs. Actual Account Problems: How to Tell the Difference
The article states “Limited by budget” often appears after switching to a more aggressive bid strategy, such as from Maximize Clicks to Maximize Conversions or lowering Target CPA, because the algorithm bids higher on individual clicks it believes are more likely to convert and consumes daily budget faster. According to groas, advertisers should wait for the learning phase to complete in 7 to 14 days before increasing budget, then assess whether higher CPCs produced proportionally better conversion rates. The article adds that a Target ROAS set too aggressively can also limit volume to a narrow subset of auctions, and recommends relaxing the ROAS target in 10 to 15 percent increments to test volume without a large efficiency loss.
Read more: “Limited by Budget” After Strategy Changes: Why It Happens and What to Do
[1] https://groas.com/post/why-your-google-ads-stopped-working-and-how-to-diagnose-it-in-15-minutes (the article this page answers from)