I remember running Spinrite regularly on my 286 as a kid in the early 90s like some sort of maintenance ritual, watching the magical blob pulsing like it was doing something deeply important. Meanwhile, each time it ran it would either 1) test a sector that had been marked bad and then unmark it as ok, or 2) test the same sector and mark it bad again.

The idea that that same app is doing something useful 30+ years later strains credulity.