Third-party marketplaces concentrate most of the world's online shopping, and the model keeps expanding: social platforms now run marketplaces, US retailers are opening their marketplaces to international shoppers, and Latin America has become the most contested battleground. This FAQ covers how marketplace power is distributed, where the growth is, and what sellers should do about it in 2026.

While we were right that retailers would offer richer in-store experiences to attract shoppers, we were wrong about how Amazon, discount retailers, and dollar stores would evolve their physical and digital strategies. From AI tools that stayed online to unfulfilled marketplace ambitions, here’s how we did with our 2025 predictions.