A client came to us after their Google Ads account spiraled out of control. They'd switched to Broad Match and Performance Max "to unlock scale," like every Google rep recommends. Budget doubled. Conversions... didn't.
When we audited the search terms, we found over $11,400 in wasted spend in just 30 days on searches for free software, job seekers, and irrelevant competitors.
This is the dilemma facing every Google Ads advertiser in 2025: Google's automation wants you to "trust the algorithm" and use broad targeting. But without proper guardrails, you'll scale into irrelevance and waste.
At Bora Media Network, we've managed millions in Google Ads spend. Here's what we've learned: The best-performing accounts don't choose between control and scale. They build guardrails that enable both. Here's how to do it.
The Problem: Google Wants Broad, You Want Profitable
Google's narrative is to use Broad Match keywords, trust Smart Bidding, and let the algorithm find opportunities. They're not entirely wrong; this can find high-intent searches you'd never think to target manually.
But here's what Google doesn't tell you: The algorithm doesn't care about your margin. It optimizes for conversions, any conversions, even the ones that cost you money.
The result is wasted spend, diluted conversion data, and budget eaten by low-intent traffic. CPAs might look "okay" on paper but hide unprofitable customers.
What "Guardrails" Actually Means
Guardrails aren't restrictions. They're strategic boundaries that keep your campaigns on track while allowing room to scale. Think of them like highway guardrails: they don't stop you from driving fast, they keep you from careening off the road.
In Google Ads, guardrails include:
- Strategic negative keywords
- Audience layering
- Bid adjustments
- Intent-based campaign structure
- Constant search term monitoring
Done right, guardrails actually improve algorithm performance by giving it cleaner data to learn from. The goal is the middle path: guided automation.
The Guardrail Framework: 5 Layers of Control
Here's the system we use to control spend without sacrificing scale:
Layer 1: Intent-Based Campaign Separation
Don't mix high-intent and exploratory traffic in the same campaign. This confuses the algorithm and misallocates budget.
- Campaign 1: High-Intent Core (60-70% Budget): Exact and Phrase Match keywords for your proven, bread-and-butter searches.
- Campaign 2: Broad Match Expansion (20-30% Budget): Carefully selected Broad Match keywords for discovery, with lower initial bids.
- Campaign 3: Brand Protection (5-10% Budget): Your brand terms and competitor conquesting.
- Campaign 4: Performance Max (10-20% Budget): Treated as supplementary, not primary, with its own budget.
This structure gives each campaign a clear job and protects your core business while exploring new opportunities.
Layer 2: Strategic Negative Keywords
The goal is to block wasteful traffic without being overly restrictive. We use a three-tier system.
- Tier 1: Universal Negatives (Account-Level): Block terms that will never be relevant, like "free," "cheap," "jobs," "careers," "course," "DIY," etc.
- Tier 2: Campaign-Specific Negatives: Apply negatives based on the campaign's intent (e.g., blocking competitor names in Broad Match campaigns).
- Tier 3: Reactive Negatives (Added Monthly): Added from weekly search term reports to block newly discovered irrelevant queries.
Layer 3: Audience Signals and Layering
Guide the algorithm toward your best customers without excluding others by adding audiences in Observation mode.
- In-Market Audiences: People actively researching solutions like yours. (Bid adjustment: +20-40%)
- Custom Intent Audiences: People who searched specific keywords or visited specific sites. (Bid adjustment: +30-50%)
- Remarketing & Customer Match: Your highest-intent audiences. (Bid adjustment: +50-100%)
- Similar Audiences: Google's lookalikes of your converters. (Bid adjustment: +10-20%)
Layer 4: Smart Bid Adjustments
Even with Smart Bidding, you can guide the algorithm with modifiers based on performance data for devices, locations, time of day, and audiences. Nudge the algorithm toward your best-performing segments.
Layer 5: Budget Pacing and Allocation
Control how aggressively each campaign spends. Allocate the lion's share (60-70%) to your high-intent core campaign. Give exploratory campaigns room to find opportunities, but ensure your best performers never run out of budget.
The Search Term Audit: Your Early Warning System
The most critical guardrail is monitoring what you're actually paying for. A weekly search term audit is non-negotiable.
- Export Search Terms (Last 7 Days): Get the raw data from Google Ads.
- Categorize Terms: Mark as Relevant (Yes/No), Intent (High/Low), and Action (Keep/Add/Negative).
- Identify Patterns: Look for waste, opportunities, and algorithm drift.
- Take Action: Add negatives for waste, add new keywords for opportunities, and adjust bids.
This simple 15-minute routine can have a massive impact, like the client who saved 28% on CPA by blocking "review" searches.
Performance Max: The Guardrail Challenge
Performance Max (PMax) is a black box, but you can still add guardrails.
- Separate PMax from Search: Use negative keywords to exclude your core and brand terms from PMax to prevent cannibalization.
- Use Strong Audience Signals: Guide PMax with your best remarketing and customer match lists.
- Use Account-Level Negatives: Apply your universal negative list to prevent obvious waste.
- Use Asset Groups for Segmentation: Separate by product category or audience for more control.
- Set Budget Caps: Don't give PMax unlimited budget. Start with 10-20% of your total and validate performance.
Our stance: PMax can work, but it should be a supplement to, not a replacement for, controlled Search campaigns.
Advanced Guardrail Tactics
Once you've mastered the basics, explore these advanced strategies:
- Dynamic Search Ads (DSA) with Tight Guardrails: Use specific page targeting and aggressive negatives to discover long-tail queries.
- Exact Match "Broad": Let Exact Match with Close Variants do the work, giving you more coverage than old exact match with more control than Broad.
- SKAGs 2.0: Group 3-5 closely related keywords per ad group for better relevance and Quality Scores.
- Competitor Conquest with Guardrails: Run competitor bidding in a separate campaign with lower bids and specific comparison landing pages.
Common Guardrail Mistakes (and How to Fix Them)
- Adding Negatives Too Aggressively: Don't block terms with low data. Only add negatives for clearly irrelevant searches.
- Ignoring Phrase Match: It's the sweet spot between restrictive Exact Match and loose Broad Match. Use it for your core keywords.
- Ignoring Search Term Reports: Make weekly audits a routine. "Set it and forget it" is a recipe for waste.
- Trusting PMax Blindly: Treat it as a supplement, not your foundation. Always run controlled Search campaigns alongside it.
Measuring Success: What to Track
How do you know if your guardrails are working? Track these metrics:
- Primary Metrics: CPA, Conversion Volume, and Wasted Spend (goal: <5% of budget).
- Secondary Metrics: Quality Score, CTR, and Conversion Rate should all improve.
- Diagnostic Metrics: Manually score search term relevance and track negative keyword counts to ensure you're not over-restricting.
The 90-Day Guardrail Implementation Plan
Here's your roadmap to roll this out:
- Month 1: Foundation and Structure. Audit your current state, restructure campaigns by intent, add universal negatives, and set up audiences.
- Month 2: Refinement and Testing. Expand with Phrase Match, implement bid adjustments, add reactive negatives, and test Broad Match carefully.
- Month 3: Optimization and Scale. Analyze performance, scale winners, tighten PMax controls, and document your new process.
By Day 90, you should see a 15-30% improvement in CPA and better lead quality.
Real Client Results: Guardrails in Action
Implementing this system for a B2B SaaS client dropped their CPA from $310 to $198 (a 36% decrease) and increased conversion volume by 22% in 90 days. For an e-commerce client, it improved ROAS from 3.2x to 4.7x. The system works.
The Future: Guardrails in an AI-First Google Ads
As Google pushes harder toward full automation, guardrails become more important than ever. They are your primary tool for steering performance when traditional levers are removed. The advertisers who master guided automation will outperform those who blindly trust it or fight it.
Getting Started Today
You don't need to implement everything at once. Start this week by running a search term report, identifying your top 10 wasted searches, and adding negatives to block them. This simple action can immediately improve your account's health.
The Bottom Line
The answer isn't to fight automation. It's to guide it with strategic guardrails. When you build the right boundaries, you get the best of both worlds: the control to spend profitably and the scale to grow your business. Your competitors are either over-controlling (limiting scale) or under-controlling (wasting money). You'll be doing neither. You'll be scaling profitably with guardrails.
Need help building guardrails that drive profitable scale? At Bora Media Network, we've implemented this system across dozens of accounts, consistently reducing CPA by 20-40% while maintaining or growing conversion volume. Let's talk.