The direct answer
Performance marketing is paid acquisition managed against a cost-per-acquisition or return-on-ad-spend target, optimized continuously rather than launched once. The two levers that move CAC most reliably are accurate attribution — knowing which spend actually drove a result — and creative testing velocity, since creative quality is one of the largest drivers of ad effectiveness.
Why most accounts plateau
Budget usually gets reallocated based on platform-level metrics like CTR or CPM, which don't reliably predict downstream revenue. Without attribution tied to actual outcomes, a team optimizes for the wrong number and CAC stalls even as spend grows.
Weekly testing beats quarterly refreshes
A monthly or quarterly creative refresh cycle generates too little data to separate a real winner from noise. Weekly testing, even at smaller volume per test, compounds into a much clearer picture of what's actually working within a quarter.
Related
See our guides on Meta vs Google ads and how to decide between ROAS and CAC as your primary metric.