Hard drive — deletion is reversible
Nothing happens to deleted data until something overwrites it. On a drive with free space, files routinely recover weeks later. Time is broadly on your side if you stop writing.
Weeks
Speed and price comparisons are easy to find and they are settled. What almost nobody covers is the failure behaviour — how much warning you get, and what can be recovered afterwards. That difference should shape how you use each.
The speed and price comparison is settled and boring. The useful question is that a hard disk usually warns you for weeks while an SSD often gives no notice at all — which changes what protects you.
The single most practical difference between the two.
A hard drive usually tells you it is dying. Reallocated and pending sector counts climb, files take longer to open, the machine freezes for thirty seconds and carries on. That period can last days or weeks, and throughout it the drive is still readable — which is a window in which you can copy everything off yourself for nothing.
An SSD usually does not. SMART reports flash wear accurately and controller health barely at all, and the controller is what fails catastrophically. A drive showing 96% life remaining on Monday can be undetectable on Tuesday, with nothing in between.
So the sensible strategy differs. On a hard drive, monitoring earns its keep because warning is actionable. On an SSD, only a backup that already exists protects you — there is no deterioration phase to catch it in.
And this catches people out constantly.
Nothing happens to deleted data until something overwrites it. On a drive with free space, files routinely recover weeks later. Time is broadly on your side if you stop writing.
TRIM tells the controller to erase those blocks, and it does so in the background while powered. That erasure is genuine and nothing retrieves it.
Donor heads, board repair, platter transfer. Invasive, well understood, and frequently successful.
Vendor mode access to the translation tables. Usually successful, and where the controller cannot be revived at all the prospects narrow sharply.
For their respective jobs.
SSDs win for anything you use daily. No moving parts means no head crash, no seized bearing, and far better tolerance of being carried around — which is why a laptop with an SSD survives knocks that would finish a spinning disk. Speed makes the machine feel entirely different.
Hard drives win for capacity and for archives. Cost per terabyte remains substantially lower at large sizes, and an unpowered hard drive retains data reliably for years. Flash does not: it stores charge behind an insulating layer, and that charge drifts away slowly when the device never gets powered — faster in older, more worn or warm-stored cells.
Which produces the practical rule that most people get backwards: an SSD in the machine, a hard drive for the archive. A USB stick or SSD in a drawer as a long-term copy is doing something the technology was never designed for.
Reallocated and pending sector counts, checked occasionally, give you genuine warning. Any pending count above zero on a drive that matters deserves attention.
There is nothing reliable to watch for the failure that matters. Assume no warning and arrange accordingly.
Neither technology makes a single copy safe, and the failure modes differ without either being rare.
A hard drive in storage benefits from being spun up now and then; a flash device left unpowered for years is the arrangement most likely to disappoint you.
In daily use, generally yes — no moving parts means no head crash or seized bearing, and far better tolerance of being carried around. The trade-off is that when an SSD does fail it usually fails without warning.
A hard drive, by a wide margin. Sector counts climb and files slow down over days or weeks while the drive is still readable. An SSD can show 96% life remaining and be undetectable the next day.
Very much so. On a hard drive, deleted data survives until something overwrites it — often weeks. On an SSD, TRIM erases those blocks physically within minutes, and nothing retrieves them.
A hard drive. Flash stores data as charge behind an insulating layer, and that charge drifts away when the device is never powered. A stick or SSD in a drawer for years is the arrangement most likely to disappoint.
An SSD, for speed and for survivability in a laptop. Keep a hard drive for the archive and the backup — cost per terabyte is far lower at capacity and unpowered retention is much better.
Not in our pricing — single drives and SSDs are both from £300 plus VAT. What differs is the probability: TRIMmed deletions and encrypted flash close some SSD cases entirely, and we establish that at the free diagnostic.