Y Combinator: Elementary Worldly Wisdom:
[Carl Braun] had [a] rule, from psychology, which, if you’re interested in wisdom, ought to be part of your repertoire — like the elementary mathematics of permutations and combinations.
His rule for all the Braun Company’s communications was called the five W’s — you had to tell who was going to do what, where, when and why. And if you wrote a letter or directive in the Braun Company telling somebody to do something, and you didn’t tell him why, you could get fired. In fact, you would get fired if you did it twice.
You might ask why that is so important? Well, again that’s a rule of psychology. Just as you think better if you array knowledge on a bunch of models that are basically answers to the question, why, why, why, if you always tell people why, they’ll understand it better, they’ll consider it more important, and they’ll be more likely to comply. Even if they don’t understand your reason, they’ll be more likely to comply.
So there’s an iron rule that just as you want to start getting worldly wisdom by asking why, why, why, in communicating with other people about everything, you want to include why, why, why. Even if it’s obvious, it’s wise to stick in the why.