EPA ratings of EV range are most likely derive from a calculation based on a range of temperatures. Thus on an annual basis, the range may be accurate. Exceeding it under optimal conditions, and failing to meet it under other conditions - like cold, inclement, windy weather; and speed. And I believe the EPA heavily depends on manufacturer data to come up with their numbers, not actually performing physical tests on all vehicles. That is why some manufacturers seem to come in with overly optimistic numbers across their range.
2018 Kia LX HEV Metal Stream with Advanced Tech