Extension cords flexible in cold weather
You may notice a child's outdoor toy blanches and cracks in 6 months from UV from sunlight, but your car's interior holds up for 20 years despite much hotter conditions.  It is a different grade of plastic.  

Also, nothing requires a cable claim every rating it's entitled to, or it may comply mostly, but fall technically short of what is needed for the rating.   You're always allowed to make a great product.