I know that you know that taking this exit will get us to Sheridan Drive, but the person who’s likely to be driving down this road in a few minutes has no idea.
Let’s agree that most street signs are for folks who know where they’re going. We would label things differently if we were instructing those that don’t.
I know that you know that ERASE isn’t the same thing as DELETE, but the next person interacting with your command-line interface might not know.
Of course this is obvious when we say it so clearly. And yet, there are many kinds of USB cables, poorly named and labeled. The instructions that come with just about anything we buy were written by lawyers for juries, not by a product manager who actually wanted to inform and delight.
Design to be understood. And design so that the inevitable confusion of the newbie doesn’t get worse. Because without your active intervention, it will.