Opening the book…
Fresh orgs are missing things that only fail at first use: the hosted parallelism grant, service connections, agent pool permissions. Each one blocks a team for a day if discovered at demo time.
On org creation: request the free parallelism grant (it is a form, and it takes days), create the service connections, set pool permissions, turn on branch policies. Do it once, on purpose, not five times by surprise.
Microsoft Learn — Configure and pay for parallel jobs — The parallelism grant request