A Tracking Code Is a More Honest Interface Than a Login
A login-gated order dashboard implies a relationship: an account, a history, an identity tied to every transaction you've ever made on the platform. For a one-off swap, that's more infrastructure than the interaction warrants, and it's infrastructure that exists to serve the platform's data collection as much as the user's convenience.
An order inquiry code does the same job, letting you check status, without implying or requiring that relationship. It's scoped exactly to the transaction it belongs to, nothing more. No password to manage, no account to eventually deal with data requests or breaches around.
It's a small interface decision, but it reflects a broader principle worth applying more often: build the minimum structure the actual task needs, not the structure that happens to be conventional.