Strother Martin in Cool Hand Luke.

When a lot of people mention Information Theory (Claude Shannon's contribution to C20), they think of comms channel capacity and number of bits per second. What Shannon was developing at a deeper level was Information = what changes beliefs and expectations (in the receivers, ie, other people). Specific beliefs and expectations, not how many words it was, but what influence it had. I'd say comms is (are) the skills of achieving that influence. Failure = a skills gap or an awareness gap about the receiver. Tom.

The important question to ask is why do we have conversations in the first place - why do we need them? To build strong reliable relationships - to belong. Relationships don't suddenly blossom, they blossom one conversation at a time over time. Relationships don't suddenly fail, they fail one conversation at a time over time. So the answer to your question - why do communications fail so often - is because conversations need to build on each other, be relevant, be consistent, be true, be worthwhile. Without these elements, failure will loom.