Strong hives that eat themselves out of house and home. Winters that are colder than expected, or longer than expected. Or maybe a poor fall bloom, so the bees started with less stores than they really needed.
It is so easy to say "feed in fall", but it is impossible to know what enough is for any one winter.
Regardless, a deadout with bees head-in their cells is most certainly a hive that starved. It was your fault.
Weighing your hives when feeding will assure you of adequate hive weights, even with extended indian summers.
Weighing each hive on a regular basis can save those hives from possible starvation, and give you hives that can make a crop in spring, rather than just setting up their own housekeeping, as is the case with nucs, splits and packages.
Only an overwintered hive can make the most of the spring blooms. The Nectar Detector costs less than even a single replacement package.