The Seagate Ironwolfs 18TB have a Workload Rate Limit (WRL) of 300TB/year, as do some WD models. Unlike SSDs this WRL includes not only writes but reads as well. (page 2, end) If you do a monthly scrub you already have 216TB of reads so it can be safely assumed that a lot of customers blow well past these numbers. This limit is in use since the 2TB drive area and simply does not fit 9x larger drives. ServeTheHome talked about this years ago.
HDDs are not unmetered warranty wise. My new 18TB Seagates has a something like 150TB/year write endurance (TBW) if I want to keep the warranty.
The Seagate Ironwolfs 18TB have a Workload Rate Limit (WRL) of 300TB/year, as do some WD models. Unlike SSDs this WRL includes not only writes but reads as well. (page 2, end) If you do a monthly scrub you already have 216TB of reads so it can be safely assumed that a lot of customers blow well past these numbers. This limit is in use since the 2TB drive area and simply does not fit 9x larger drives. ServeTheHome talked about this years ago.