10 Costly mistakes your Meta Ads agency makes (spot them)

Meta advertising has changed drastically over the past few years. The best practices that worked flawlessly in 2021 are directly harmful to your returns today. Yet, at Iternum Digital, we frequently see advertisers and agencies stubbornly clinging to outdated strategies. This results in wasted ad spend, an unnecessarily high CPA (Cost Per Acquisition), and a ROAS (Return on Ad Spend) that looks better on paper than it does on the bottom line.

If your business is investing serious money into Meta advertising, it is crucial that your setup is up to date. We have compiled 10 classic mistakes that we often encounter when taking over and auditing existing ad accounts. Use this list as a checkpoint to evaluate whether your current setup is driving your business forward or holding it back.

1. You don't own your own data and assets

This is perhaps the most frustrating mistake for a business owner. When an agency sets up your advertising, they often create the ad account, your Meta Pixel, and link Facebook pages within their own Business Manager (now called Business Portfolio).

This means the agency effectively owns your most critical assets. If the partnership ends one day, you risk losing all your history, collected data, and machine learning. At Iternum Digital, we operate with full transparency. It is an absolute requirement that the client owns their own Business Portfolio and all associated assets. The agency should simply be added as a partner with the necessary permissions. This way, you are never locked in, and your valuable data stays within your company.

2. Missing definition of "Audience Segments"

A quick glance at the account settings can often reveal the quality of the previous work. If the “Audience Segments” section is left blank, it is a red flag.

When these segments are not defined, you (and your agency) have no real insight into how much of your budget Meta’s algorithm is automatically spending on remarketing within, for example, Advantage+ Shopping campaigns. Without this knowledge, you cannot evaluate whether your ads are primarily generating net-new sales or simply hitting people who were already on their way to making a purchase. A correct definition of engaged audiences and existing customers is essential to understanding how your money is distributed.

3. Too much focus on remarketing (and inflated results)

It is tempting to throw a large portion of the budget into remarketing because it often produces spectacular ROAS numbers in reports. But you need to be critical here. If your agency relies too heavily on remarketing—especially targeting your email list or cart abandoners – you are potentially paying for conversions that would have happened anyway.

This issue is amplified by Meta’s attribution models. A conversion can be counted simply because a user saw the ad (View-Through) or interacted with it (Engage-Through) without actually clicking through to your webshop. We focus on incremental growth. It’s not about making the numbers in Ads Manager look pretty; it’s about ensuring that your ad spend actually generates tangible value on the bottom line.

4. Unnecessary restrictions on age, gender, and placements

A common misconception is that you need to narrow down the audience manually to hit your “ideal customer.” Many agencies consistently exclude specific age groups, genders, or ad placements like the Audience Network, assuming it optimizes the budget.

Today, however, Meta’s Advantage+ algorithm is incredibly skilled at finding the users most likely to convert on its own. By imposing unnecessary manual restrictions on the algorithm, you limit the system’s ability to learn and find the cheapest conversions, which inevitably drives up your CPA. Instead of blocking segments manually, you should use “Value Rules” to guide the algorithm toward your most valuable customers while maintaining a broad and flexible targeting approach.

5. Overly complex campaign structure

When auditing accounts, we often see a jungle of campaigns and ad sets, even with relatively modest budgets. Traditionally, the idea was to isolate specific audiences to maintain control.

The problem is that this approach dilutes the budget. For Meta’s algorithm to deliver stable and predictable results, an ad set should ideally generate around 50 conversions per week to exit the “Learning Phase.” If the budget is spread thinly across ten different ad sets, none of them will receive enough data to optimize effectively. In most cases, a simplified and consolidated campaign structure is the way forward to ensure optimal machine learning and lower conversion prices.

6. Old-school A/B split testing of ads

Five years ago, it made sense to test one headline against one specific text and one image in separate ad sets. That type of manual micro-management is outdated today.

A modern Meta ad functions more like a dynamic container. You can (and should) input multiple headlines, texts, and creatives into the same ad, after which Meta mixes and matches them to deliver the version that resonates best with each individual user. As we have previously described in connection with Meta’s Andromeda rollout, the quality of your creatives is the primary driver of targeting. An agency’s time is much better spent developing high-impact, attention-grabbing content rather than monitoring hundreds of outdated A/B tests.

7. Focus on "soft" metrics instead of business value

If your agency is reporting success based on the number of link clicks, ThruPlays (video views), or general engagement, alarm bells should be ringing. Meta’s algorithm is extremely literal. If you ask it to get cheap clicks, it will find the users who click on everything—but rarely buy anything.

In the vast majority of cases, your advertising should be optimized for the action that actually drives value for your business: purchases or qualified leads. Optimizing for soft metrics is a classic mistake that results in plenty of traffic but no measurable impact on revenue.

8. Flawed tracking – blindly relying on the browser pixel

A setup that relies solely on Meta’s browser-based pixel is insufficient today. Following Apple’s iOS 14 update, up to 60–70% of iOS users opted out of cross-app tracking, and ad blockers actively prevent the pixel from firing. This creates a systematic blind spot in your data, giving the algorithm a distorted picture of who is actually converting.

The solution is the Meta Conversions API (CAPI)—a server-side integration that sends conversion data directly from your server to Meta, bypassing the user’s browser. The recommended setup combines the pixel and CAPI, allowing Meta to deduplicate the two data streams. A key element here is the Event Match Quality (EMQ), a score from 0 to 10 that measures how accurately Meta can match a conversion to a user. A low EMQ score means the algorithm is optimizing based on poor data, directly increasing your CPA. Ask your agency: What is our EMQ score, and are our conversion events configured to reflect our actual business goals?

9. Too few creatives and lack of creative diversity

Many agencies deliver two to three creatives per campaign and call it a test. In 2026, that is not a test—it is an insufficient foundation for an algorithm that requires variation to optimize effectively. As mentioned in point 6, old-school A/B split testing is outdated. However, the problem goes beyond the testing method; it is equally about the overall volume and breadth of creative material continuously fed into the account. According to Meta’s official blog post on creative diversification from December 2025, campaigns that actively utilize creative diversification achieve an 11% higher click-through rate and a 7.6% higher conversion rate.

The challenge is two-fold: volume and diversity. Experienced advertisers recommend starting with 10–20 distinct creative variations per ad set. But simply having multiple versions of the same creative with a slightly different headline is not enough—the Andromeda algorithm actively scans for visual and conceptual similarities, and creatives that look too much alike are treated as variants of a single creative. The algorithm needs genuine diversity across formats, angles, and emotional hooks. When creatives wear out and the frequency rises above 3–4 exposures per user within seven days, ad fatigue sets in: CPM increases, click-through rates drop, and CPA climbs. A professional agency should have a structured creative pipeline and a clear plan for when to introduce new creatives.

Source: Meta for Business – “Demystifying Creative Diversification”, December 2025.

10. Mismatch between ad and landing page

A high click-through rate combined with a low conversion rate is almost always a symptom of the same issue: the ad and the landing page are telling two different stories. When a user clicks based on a specific promise—a discount, a solution, a product—and does not immediately find that promise validated on the landing page, cognitive dissonance occurs. The hesitation is enough to trigger a bounce, wasting your ad spend. Research shows that proper alignment between an ad and its landing page can lift conversion rates by up to 31%.

Alignment comes down to four things: message, visual identity, offer, and mobile performance. The landing page headline must reflect the core message of the ad, the visual style must be recognizable, and the specific offer must be visible above the fold, not buried in a footer. Furthermore, 53% of mobile users abandon a page that takes more than three seconds to load. Many agencies also send all traffic to the homepage rather than a dedicated landing page tailored to the ad’s message. At Iternum Digital, we view the ad and the landing page as a single cohesive system, not two separate responsibilities.

Is your setup ready for the future?

Navigating an advertising landscape that is constantly evolving can be complex. If you recognize one or more of the above mistakes in your current setup, there is a high probability that you are paying too much for your conversions. At Iternum Digital, we specialize in cleaning up outdated setups and driving transparent, data-driven, and high-performing growth for our clients.

Would you like an analysis of your current setup and strategy?

We are currently offering a free audit of your ad account to evaluate whether your budget is being utilized optimally and where your greatest growth opportunities lie. Contact us for a non-binding chat about how we can future-proof your Meta advertising.

Not sure if your money is being spent wisely?

Don’t let outdated strategies eat into your profits. Feel free to call or write to us for a no-obligation review of your Meta ad account. Let’s identify your hidden growth opportunities and ensure your setup is geared for the future.

Daniel Jakobsen

Senior Social Media Consultant

daniel@iternumdigital.com

+4532121100

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