Fraud review should not begin only after a campaign has already underperformed. Buyers who monitor a few basic signals early usually catch inventory problems before they become a budget story.
Traffic that clicks but never behaves like a real user deserves attention. Extremely short sessions, identical browsing patterns, or strange conversion timing can reveal quality issues even when top-line delivery appears normal.
Fraud rarely distributes itself evenly. Reviewing by placement, device, geography, and time window helps isolate suspicious pockets faster than looking at blended campaign metrics.
Perfectly uniform performance is often as suspicious as obviously bad performance. Real traffic usually contains variation, especially across creatives and placements.
Fraud prevention is an operational habit, not a one-time audit. Buyers who combine source review, engagement analysis, and ongoing exclusions build campaigns that stay scalable for longer.
