A multi-region launch is not the same program run more than once. It is a set of programs with shared components and divergent requirements, and treating it as the first thing is how you underestimate it.
The divergence lives in regulation, payment method, data residency, and support language. Those are not engineering decisions. They are program inputs that determine what the engineering decisions can be. Discovering them late means rework. Discovering them in the planning phase means design choices.
At Roku, expanding the payment platform internationally meant that what worked with Adyen in North America required different settlement logic, different reconciliation windows, and different fraud rules by region. None of that was in the original scope. All of it had been discoverable with earlier stakeholder engagement. I found it six weeks into build, which is the most expensive place to find it.
The planning tool that works for multi-region is a requirements matrix: one row per region, one column per requirement category. Regulation, payment, data, language, support. Cells that are identical across regions become shared work. Cells that differ become separate tracks. That matrix is what shows you what you actually have to build.
Launch sequencing matters more than launch simultaneity. A phased regional rollout with a real feedback loop between regions is almost always better than a simultaneous global launch. The first region to go live teaches you what the others need before they go live.