When a German data recovery firm recently made a study of the failed flash storage drives it had been sent, it noticed some interesting bad trends.
Most of them were cheap sticks, the kind given away by companies as promotional gifts, but not all of them. What surprised CBL Data Recovery was the number of NAND chips from reputable firms, such as Samsung, Sandisk, or Hynix, found inside cheaper devices. The chips, which showed obvious reduced capacity and reliability on testing, had their manufacturers' logo either removed by abrasion or sometimes just written over with random text.
Sometimes there wasn't a NAND chip at all, but a microSD card—possibly also binned during quality control—scrubbed of identifiers and fused onto a USB interface board. On "no-name" products, there is "less and less reliability," CBL wrote (in German, roughly web-translated). CBL did find branded products with similar rubbed-off chips and soldered cards but did not name any specific brands in its report.