Comment by bryanrasmussen

inefficiency often creates redundancy, but they are not synonyms.

Redundancy may be inefficient, but you can also build redundant systems that looking at from a micro perspective seem inefficient but what you see is only a local inefficiency; if you distribute their effects far enough in space and time you find that they are actually at a macro scale more efficient than not having them because they prevent breakdowns that destroy all the smaller systems held within the bigger one.