Secure OAuth is easy to demo and hard to operate at scale
Most teams think about OAuth the same way they think about logging. It is necessary, familiar, and supposedly solved. Then it hits production. Suddenly, it is not just one authentication flow. It is a complex web of two or more applications, multiple environments, cookies, redirects, secrets, and route boundaries. The uncomfortable truth is that OAuth security is not just an implementation detail. It is an operational system, and that system is only as strong as the platform it runs on.