Redundancy Helps Us Communicate Better

Communication is noisy, particularly if the person you're talking to is not paying very close attention. The same thing could happen if our brains were somehow better and we had more attentional focus. We can strike a balance between how much effort we're prepared to put in and how much slop we're allowed to tolerate. This is what redundancy helps us do. If we didn't have redundancy in our communication, we wouldn't have the option to be lazy because we'd have to be constantly paying perfect attention.