Sometimes, it's essential that you be completely understood. That every passenger knows where the emergency exit is, or that every employee knows how it is we do things around here.
But most of the time, if 2% of your audience doesn't get the joke, doesn't learn what you seek to teach them, doesn't understand the essence of your argument, it's not the problem you think it is.
Sure, the 2% who are underinformed can write reviews, tweet indignantly and speak up. You know what? It doesn't matter that much.
If you insist on telling everyone on the airplane precisely how to buckle their seatbelt (!), then yes, of course you're going to not only waste the time of virtually everyone, but you're going to train them not to listen to the rest of what you have to say.
If you insist on getting every single person in the room to understand every nuance of your presentation, you've just signed up to bore and alienate the very people you needed most.
When you find yourself overwriting, embracing redundancy and overwhelming people with fine print, you're probably protecting yourself against the 2%, at the expense of everyone else. (And yes, it might be 10% or even 90%…. that's okay).
When we hold back and dumb down, we are hurting the people who need to hear from us, often in a vain attempt to satisfy a few people who might never choose to actually listen.
It's quite okay to say, "it's not for you."