Using a multi-tape archive increases your chance of failing to restore. Rather than having one possible tape that can be corrupt, you know have more than one.

Using a multi-tape archive increases your chance of failing to restore. Rather than having one possible tape that can be corrupt, you know have more than one. Any single failure will corrupt the whole archive, and you've lost (easy access to) the data. Better to break up the source volume somehow, and have each tape self-contained.