 This early signal allows the main computer to continue working even though the data has not actually been written yet.This can be somewhat dangerous, because if power is lost before the data is permanently fixed in the magnetic media, the data will be lost from the disk buffer, and the file system on the disk may be left in an inconsistent state.On some disks, this vulnerable period between signaling the write complete and fixing the data can be arbitrarily long, as the write can be deferred indefinitely by newly arriving requests.