The attributes are genuinely accurate about flash wear — and flash wear is not what usually kills an SSD. The controller is, and almost nothing in SMART sees it coming.
Percentage used, reserved or reallocated blocks, and uncorrectable errors. Watch those and you have the picture; the several dozen other attributes mostly tell a normal user nothing actionable.
SSD self-monitoring reports flash wear reasonably well and controller health barely at all — and it is the controller that usually fails. That is the central problem with checking SSD health: the thing most likely to kill your drive is the thing SMART is worst at seeing.
So a drive reporting 96% life remaining is telling you its flash has plenty of write endurance left. It is not telling you the controller will still be responding tomorrow, and it has no way of knowing.
This is why SSDs fail without warning while hard drives announce themselves for weeks, and why the backup regime matters more on solid state than on anything else.
Percentage used, or wear levelling count. How much of the rated write endurance has been consumed. Useful for planning replacement, useless for predicting sudden failure.
Total host writes. Compare against the drive's rated TBW. A drive well inside its rating that is misbehaving has a controller problem, not a wear problem.
Available spare, on NVMe. Reserve blocks remaining. A falling spare count is one of the few genuine warnings solid state gives.
Temperature history, where reported. Sustained heat is the most consistent factor across the NVMe failures we see, particularly in thin laptops and unventilated M.2 slots.
From wear, yes. From controller failure, that figure tells you nothing, and controller failure is what usually happens.
Largely no, and that is the honest answer. There is no equivalent of the noises a hard drive makes. Back up accordingly.
Rarely. Consumer drives are usually replaced long before the flash exhausts itself. The controller failed instead.
It is the most consistent factor we see across NVMe failures. It does not change the recovery method, but it explains a lot of them.