Vertical versus Horizontal Communication
Have you ever been told, "I gave you all the information the first time. Why can't you get it into your head?" Or perhaps you were the one that said it?
Everyone has a different way of assimilating information into their brain. The mistake is in assuming your method of communication works for everyone. The idea behind "vertical" communication is that you moderate the amount and form of communication to better accommodate a diverse audience. Whereas a "horizontal" message presents all the facts at once and have a dense context, a vertical message will present fewer at a time and build on the context as it goes.
Human tendency is to communicate horizontally. In our rush to get out the message, we cram as much information as will grammatically fit into a sentence, add a parenthetical hint of context, throw in a crescendo of inflection for emphasis and all before drawing our first breath. It doesn't occur to us how much of a burden this places on our listeners, who are struggling to catch up to your conversation. To the contrary, some of us might erroneously take the listener's shortfall as a sign we are on a higher plain of understanding.
To be effective, communication needs to be moderated to the listener, not the speaker. In essence, the person doing the talking needs to consider the possibility that his message may not be presented well. I like to call that manners, but it isn't always seen that way.
Personally, I find it fun to craft my message to my audience. Covey's notion of perspective counts for something there, and it's really just an outer bound of context. I'll start using keywords up front to couch what follows and to add interest, which in turn provokes better listening. It's like having subheadings or crafting ad copy.
What if you insert a question to provoke even more attention and assimilative thought? By answering the question themselves, listeners assimilate information better than if you just give them the answer.
When you find yourself tired and frustrated enough to subscribe to the myth that anyone can understand you if you speak slowly and loudly enough, then remember it's your responsibility to make your words meaningful — before you can expect the listener to accommodate your lack of information.