The novice took an old backup tape to the backup master and asked: "Master, this tape is six months old. If I am to achieve oneness with the Earth, is it not right that it be re-used?"
The master took the tape and said: "I will re-use it. Now, quickly, go and examine your disk drive."
The novice examined his disk and discovered that a virus had corrupted hundreds of important, but rarely-used files. He loaded a day-old backup, but found that those files were corrupted too.
He loaded the week-old backup, but it was the same. Eventually, he realized that the virus had struck four months before. He returned to the master and said: "Master, you have the only uncorrupted copy!"
But the master had already overwritten it with a copy of DOOM.
The master said: "Just as we respect and care for our ancestors, so we must respect and care for our old backups, for one day they may achieve great glory."