What it means
Instead of finding new strangers (prospecting), retargeting re-engages a warm audience that already knows you: visited a product page, added to cart, watched 50% of a reel. Because intent is high, conversion rates and ROAS look great.
Why it matters
It is essential but seductive. Retargeting often reports the best ROAS in the account — which tempts teams to pour budget into it. But much of that conversion would have happened anyway (see incrementality). Use it to close demand, not to manufacture it, and cap frequency so you do not stalk people into resentment.