[JackFr]

You assume failures are uncorrelated. Which, depending on what you think you are protecting yourself from, might or might not be true.

(Consider a buggy software release which incorrectly deletes a backup. Depending on the bug it’s very possible it will delete in both places.)

[bee_rider]

If one buggy software release can delete both copies, then you don't have actual redundancy from the point of view of that issue.