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    KnowledgeNovember 7, 20263 min read3

    Scaling Google Demand Gen: Why You Must Split Campaigns Instead of Ad Groups

    Stacking ad groups inside a single Demand Gen campaign causes Google to dump budget into cheap audiences. Minh explains why splitting campaigns is essential to scale.

    When scaling Demand Gen campaigns in Google Ads, many advertisers instinctively create multiple ad groups inside a single campaign to test different audiences. In practice, budget distribution rarely splits evenly. Instead, Google's algorithm frequently funnels the vast majority of spend into a single group, leaving the remaining audiences starved of impressions.

    This behavior stems from Google's auction mechanics. Machine learning prioritizes auction inventory that is cheapest and easiest to fulfill to hit daily budget targets, rather than distributing spend evenly toward high-intent audiences that carry higher auction costs.

    1) Splitting campaigns to retain budget control

    If you host several ad groups within one campaign, Google naturally favors the least competitive segment. The proven workaround is isolating each audience segment into its own distinct campaign. By granting every audience a dedicated budget, you ensure guaranteed delivery while understanding how Google automated bidding distributes budget to intervene when necessary.

    2) Scaling audiences by intent tier

    When building separate campaigns, scaling should follow a strict hierarchy starting with Competitor Custom Intent. Targeting users who search for direct competitors, competitor brand names, or landing pages delivers the highest conversion readiness. Once saturated, budget can expand into comparison queries and problem-solving terms, following the framework of scaling Google Ads profitably without breaking margin.

    Minh encountered this exact pattern repeatedly when managing multi-market Google Ads campaigns at Kyna English and B2B global accounts at QH Distribution. In competitive markets, allowing algorithms unchecked discretion between existing audiences and broader segments inevitably diverts capital into low-cost, low-quality impressions that generate minimal qualified pipeline.

    3) Tailoring messaging to funnel depth

    Campaign isolation also unlocks granular creative alignment. Prospects evaluating competitors require feature proof points and comparison charts, while early-stage researchers need educational problem-solving creative. In essence, testing Google Ads creatives across defined segments succeeds only when audience targeting is cleanly segregated.

    The key lesson: Scaling Demand Gen predictably requires deliberate structural segmentation rather than relying solely on automated audience allocation.

    Frequently Asked Questions

    Why is combining multiple ad groups in a single Demand Gen campaign ineffective?
    When multiple ad groups share one campaign budget, Google's algorithm naturally favors segments with cheaper ad inventory and lower auction friction to exhaust daily spend quickly. This starves higher-value, high-intent audiences of impressions, reducing the overall conversion efficiency and lead quality of the campaign.
    Which audience segment should advertisers prioritize when scaling Demand Gen?
    Advertisers should start with Competitor Custom Intent targeting users searching for direct competitor brand names, products, or URLs. This audience demonstrates verified commercial intent and yields faster conversions, generating steady returns before expanding into broader problem-solving or comparison keywords.
    How much budget is needed to scale with separate Demand Gen campaigns?
    Each standalone campaign requires sufficient budget to generate roughly 20 to 30 conversions per month for Google's machine learning models to optimize effectively. Instead of splitting a small budget across numerous campaigns at once, scale each campaign sequentially as conversion thresholds are reached.

    About the Author

    Trần Quang Minh
    Trần Quang Minh

    Digital Marketing / Performance Ads Expert

    9+ years in Digital Marketing. Expert in Google Ads, Facebook Ads, TikTok Ads, SEO. Helped businesses grow revenue up to 500% and organic traffic from 3K to 120K/month.

    DND Eye Hospital, ELSA, Kyna, 51TalkLecturer at Hoa Sen University
    Scaling Google Demand Gen: Why You Must Split Campaigns Instead of Ad Groups | Blog Trần Quang Minh