Several of the DragonFly machines used for building packages and/or releases have SSDs, and have been vigorously exercising those disks for some time. SSDs are supposed to have a shorter lifetime than spindle-based hard drives. However, Matthew Dillon found that there’s surprisingly little wear on those SSDs. This empiric information was noticed in several places.
A running description of activity related to DragonFly BSD.
Some time ago I visited a forum where the occupants deliberately tested SSDs to destruction.
It may not apply to all brands, or technology may have moved on since, but they found that generally SSDs don’t die, they just lose their ability to hold a charge (i.e. the data).
In their tests, if you didn’t power the machine down, the drive continued to work long after its expected death date.
The problem was that without any prior sign of an issue, if the machine had to be powered off for any reason, the drive had disappeared upon restart.