This jargon suggests that the scope and complexity of your "epics", "milestones" and "features" are abnormally unsurprising and consistent. Is it because whoev

This jargon suggests that the scope and complexity of your "epics", "milestones" and "features" are abnormally unsurprising and consistent. Is it because whoever defines them is very good at detailed estimates, or because the work is repetitive and predictable, or because the deadlines are weak and elastic?