Creative volume is the only durable lever. Give the algorithm 15+ genuinely different creatives, clean CAPI signal, and broad targeting, then let Motion tell you what to kill and what to scale.
Creative volume is the targeting strategy. One Advantage+ Shopping Campaign, broad audience, CAPI-grade signal, 15+ creatives in rotation, read Motion weekly and replace the fatigue cases. Not doing: interest layers, multiple campaign structures, or manual bid overrides before the algorithm has stabilised.