Nothing when mockups are iterable and editable by the team and when the designer is part of the team. A hell of useless code/new APIs/authorization issues just

Nothing when mockups are iterable and editable by the team and when the designer is part of the team. A hell of useless code/new APIs/authorization issues just for no customer value but only discutable esthetics considerations when mockups are designed up front by some never available designer like they are some inviolable part of the specifications thus are enforced to the team.