There is a limit of ten tokens that are issued per user/application/scope combination, and a rate limit of ten tokens created per hour. If an application creates more than ten tokens for the same user and the same scopes, the oldest tokens with the same user/application/scope combination are revoked. However, hitting the hourly rate limit will not revoke your oldest token. Instead, it will trigger a re-authorization prompt within the browser, asking the user to double check the permissions they're granting your app. This prompt is intended to give a break to any potential infinite loop the app is stuck in, since there's little to no reason for an app to request ten tokens from the user within an hour.