I've read somewhere, that I can't find at the moment, that Apple expects/promises that Mac batteries will retain 80% capacity after 1000 cycles, and iOS devices

I've read somewhere, that I can't find at the moment, that Apple expects/promises that Mac batteries will retain 80% capacity after 1000 cycles, and iOS devices will retain 80% after 500 cycles. The lower cycle number for iOS devices is presumably due to them being exposed to higher temperatures (in pockets e.g.) and not having any active cooling to counter this.