[throwaway8941]

It does, when your crappy hardware doesn't lie to the kernel. Go take a look at the amount of unrecoverable FS corruption discussions at LKML. It still happens relatively frequently, and is almost always caused by shitty hardware ignoring fsync and lying to the filesystem. SD cards and cheap SSDs are especially terrible in this regard (that's why I refuse to buy anything except from the most respected vendors, and they still have their issues). Many devices don't even report checksum mismatches on read requests and simply return garbage data, and most filesystems don't notice it (because they don't implement a data integrity checking mechanism of their own)