Most analytics tools weren't built for a brand selling on Otto, Zalando, Kaufland, and Shopify at the same time. They were built for a US brand on Shopify and Amazon.com, and the German marketplace stuff got bolted on later, if at all. If you're running ecommerce analytics Germany DTC brands actually need, the gap shows up fast: VAT gets handled inconsistently, marketplace payouts don't reconcile against ad spend, and your "blended ROAS" number is quietly wrong. Here's what actually works instead.