SSDs tend to have highly correlated failure modes because you either run into a bug in the firmware which is the same on every SSD or you have the same wear on

SSDs tend to have highly correlated failure modes because you either run into a bug in the firmware which is the same on every SSD or you have the same wear on every SSD, which locks both into read-only mode within a short period of time. You might argue that read-only is not a failure, but read-only means downtime and replacing hardware.