I think they go with a write cache.<p>I recall some distros tried to mount USB drives with the sync option back in the early days of USB media.<p>Problem was that this, in combo with FAT, would basically kill cheap drives lacking wear leveling.<p>This because every write action was accompanies with a allocation table update. And thus whatever flash cells housed that table would see a massive amount of writes.<p>Actually i think the mount man file still have a warning about this in the sync option entry.