Editing Data degradation (section)

====Solid-state media====
[[EPROM]]s, [[flash memory]] and other [[solid-state drive]] store data using electrical charges, which can slowly leak away due to imperfect insulation. Modern flash controller chips account for this leak by trying several lower threshold voltages (until [[Error correction code|ECC]] passes), prolonging the age of data. [[Multi-level cell]]s with much lower distance between voltage levels cannot be considered stable without this functionality.<ref name="Li_2022"/>

The chip itself is not affected by this, so reprogramming it approximately once per decade prevents decay. An undamaged copy of the master data is required for the reprogramming. A [[checksum]] can be used to assure that the on-chip data is not yet damaged and ready for reprogramming.

The typical SD card, USB stick and M.2 NVMe all have a limited endurance. Power on can usually recover data{{Citation Needed|date=January 2025}} but error rates will eventually degrade the media to illegibility. Writing zeros to a degraded NAND device can revive the storage to close to new condition for further use.{{Citation needed|date=February 2025}} Refresh cycles should be no longer than 6 months to  be sure the device is legible.