Teams that want to protect their catalog, pricing, or review data often start with one fix: a rate limit, a CAPTCHA, a robots.txt rule. Then the traffic keeps coming. The reason is simple. Large marketplaces like Amazon do not rely on one control. They stack several, each catching what the previous one misses. If you run a site with valuable product data, that layered model is the one worth copying. Why one control is never enough Every single defense has a known workaround.