Think of your funnel like a tower: the bottom is what holds everything together. If the base is weak, the entire structure becomes unstable, no matter how strong or beautifully designed the top floors are.
Your bottom funnel works the same way. It’s the foundation of your growth, where real outcomes finally happen, purchases, sign-ups, subscriptions, and revenue.
But when fraud creeps into this stage, the damage is far greater than just a few bad metrics. It shakes the entire system.
A compromised BOFU means you are building success on numbers that don’t exist. And when the foundation is fake, everything that depends on it eventually falls apart.
In this blog, you will discover –
- The two major BOFU fraud traps
- How click fraud distorts final conversions
- How incent fraud fakes success
- Warning signs your BOFU metrics are corrupted
- Steps to rebuild BOFU integrity
Click Fraud: Fake Click Journeys That Mislead Optimization
Click fraud is no longer just a top-funnel nuisance. Modern fraud networks simulate entire user journeys where the impact extends to bottom-funnel as well. The sophisticated kind of click fraud impacts bottom of the funnel metrics with the following fake clicks methods –
Click Spamming
When fraudsters fire multiple fake clicks often through device simulators or bulk click scripts, they clutter the system until a real user eventually installs the app. Because this happens within the attribution window, the system mistakenly credits the install in fraudster’s name. This click spamming skews your bottom-funnel metrics by turning genuine installs into “paid” conversions, inflating acquisition costs and hiding true organic performance.
Click Injection
Click injection is an advanced form of click fraud where a malicious app tracks when a real user is about to install another app and fires a perfectly timed fake click just moments before the install completes. Because the timing appears legitimate, the attribution system credits the fraudster for the install, corrupting bottom-funnel metrics and misleading optimization algorithms toward fraudulent sources—ultimately polluting the stage where real revenue and true performance should be measured.
Impacts of Fake Clicks on Bottom of the Funnel Metrics
Fake clicks severely damage the conversion stage due to the following impacts –
Inflated CTR & Depressed Conversion Rates
Fake clicks spike Click Through Rate (CTR) but never convert, making genuine add-to-cart, sign-up, app install, and purchase rates look significantly weaker.
Budget Drain & Higher Cost-per-Activity
Fraud wastes spend on non-human traffic, pushing up CPA and reducing the volume of real users who reach the bottom funnel.
Polluted Retargeting Signals & Skewed Optimization
Bots enter remarketing pools and send false engagement signals, causing ad platforms to optimize toward low-quality audiences.
Distorted Attribution & Misleading Performance Metrics
Click fraud manipulates what looks “effective,” misguiding decisions across channels, creatives, affiliates, and campaign strategy.
Inaccurate ROAS Projections & Direct Revenue Loss
With fake interactions replacing real intent, projected ROAS becomes unreliable, actual conversions drop, and long-term revenue suffers.
Incent Fraud: Incent Traffic That Looks Real but Acts Fake
Incentivized traffic, or incent traffic, happens when fraudsters run incentive campaigns to attract users by offering points, cash, discounts, or in-app currency for completing actions like clicking an ad, installing an app, or signing up. This creates incent fraud, where actions look real on paper but come with no genuine interest or long-term engagement. Incent walls, often seen in reward apps, fuel this by offering perks in exchange for installs or tasks. While incent traffic may seem like a quick way to boost numbers, it becomes a problem for advertisers who want quality users, because these “reward-driven” installs rarely convert, engage, or deliver true value.
Common Methods of Incent Fraud
Fraudulent affiliate cause incent fraud through following common methods –
Sub-affiliate Routing
Dishonest affiliates cause affiliate marketing fraud where they pass incent traffic through multiple sub-affiliates, so it looks “organic,” hiding the fact that users were rewarded to perform the action.
Device Farms
Workers install farms that repeatedly install/uninstall apps on many devices to mimic real users and generate fake conversions.
Know more about device fraud damaging your ROAS
Device Fingerprinting Manipulation
Changing device IDs, IPs, or system parameters to make one device appear like multiple unique users, inflating installs or events.
Proxy/VPN-Based Identity Masking
Using proxies or VPNs to switch IP addresses so fraudsters can imitate traffic from different locations and avoid detection.
Impact of Incent Fraud on Bottom of the Funnel
- Biased Engagement Metrics: Fake or uninterested users distort event-level KPIs (add-to-cart, sign-ups, purchases), making optimization harder.
- Wasted Retargeting Spend: You end up retargeting wrong users who never intended to convert, burning remarketing budgets.
- Misleading Attribution Signals: Incent traffic inflates lower-funnel events, causing attribution platforms to credit the wrong partners or campaigns.
5 Signs Your Bottom-Funnel Metrics Are Getting Polluted
Top warning signs that brands can watch out to identify if their bottom of the funnel is getting polluted –
- CPA/CPI rising with no improvement in quality
- LTV tanking even though installs look strong
- Retention dropping sharply after Day 1
- Events coming in “too perfectly” or unusually fast
- Top-performing sources delivering zero real revenue
- Algorithms optimizing toward partners that don’t scale
How to Reclaim Your Bottom-Funnel Integrity
To protect the lower funnel, brands need more than top-funnel detection. They need to shift from “Is this click valid” to “does this behavior make sense end to end?” Here comes mFilterIt’s Valid8, an ad fraud detection software that safeguard brands through –
- Click-to-install pattern analysis: Identifies abnormal click and install behaviors so you can spot fraud early and ensure only genuine installs are counted.
- Device identity integrity checks: Validates real devices and filters out spoofed, cloned, or manipulated ones, keeping your bottom-funnel data clean.
- Incent traffic classification: Separates organic users from incentive-driven ones, helping you protect quality and prevent inflated performance metrics.
- Uninstall velocity monitoring: Tracks how quickly users uninstall after installing, revealing fake, forced, or low-intent traffic instantly.
- End-to-end source clarity: Gives you full visibility into where each install, click, and event is coming from, removing blind spots in attribution.
- User intent scoring: Measures the true intent behind user actions, helping you prioritize high-quality users and reduce wasted spend.
With the right ad traffic validation platform, marketers can finally distinguish between:
- Real users vs. scripted users
- Genuine conversions vs. incentivized behavior
- Authentic engagement vs. manipulated KPIs
- Legit installs vs. farmed installs
Conclusion
Your bottom of the funnel shapes everything that happens above it. If what flows into your top funnel is already polluted with fake users, invalid clicks, or low-intent traffic, your entire marketing engine starts making the wrong decisions. That’s why maintaining bottom-funnel hygiene isn’t optional—it’s the foundation of accurate attribution, reliable CAC, and meaningful conversions.
Don’t let fraudulent activity dilute the results you’ve worked so hard to achieve. With the right ad fraud detection software like mFilterIt’s Valid8, you can ensure only genuine, high-quality, and verifiable actions enter your funnel. Clean signals lead to smarter optimization, stronger ROI, and sustainable growth.
Want to see how it works for your campaigns? Schedule a quick discovery call now.
FAQs
What is incentivized traffic and why is it harmful?
Incent traffic comes from users who take actions only for rewards. They look real on paper but don’t engage, convert, or retain, corrupting BOFU data and wasting budget.
How incentivized ad fraud works?
Fraudsters drive installs or actions purely for rewards using device farms, fake users, or sub-affiliate routing, making low-intent activity look organic.
How does click fraud impact bottom-funnel metrics?
Click fraud injects fake click journeys that get falsely credited with installs or conversions, inflating CTR, depressing real conversion rates, and misleading optimization algorithms.
