Can you pitch your idea or make your point in the length of an elevator ride? That’s been a long-standing and effective thought experiment to help determine if you’ve thought clearly enough about your plan and can articulate it simply and quickly.

So, if you’re working on a speech or a business idea or a movie script or trying to start a movement to change the world, consider the elevator test.

Imagine you’re giving a talk at a conference. A fellow attendee gets on the elevator with you and sees the “Presenter” ribbon on your name badge. He lets you know he’s tempted to escape the conference during your session and go play golf or take a nap and asks what he would miss from your talk. What would be your response? What will your talk accomplish that would be of value to this wayward golfer? What will offer him enough value to make him delay his escape and stay for your presentation?

If you can’t come up with a short simple statement of your intended purpose and one that offers something of value to the prospective audience member, you need to go back to the beginning and rethink just why it is you’re doing this presentation. Or starting a business. Or writing a screenplay. Or starting a movement.

Or, instead of an elevator pitch, my 21st-century, connected friends, consider the challenge of tweeting, in 140 characters or less, your purpose, your mission, your goal. Can you say in just a few words, within the constraints of a tweet, what you hope to accomplish? If not, get busy asking “Why?” and hone and sharpen your thinking to come up with as clear and simple a statement as you can.

Here, for example, in tweet form (and exactly 140 characters thanks to the added hashtag and a stray space, because I’m just OCD enough), is my aim for a talk I’m giving this week to a couple of college classes:

So many companies and organizations have some committee created mission statement that is either unknown and ignored or is so unwieldy as to be meaningless. What if your mission statement was tweetable and so direct and clear that everyone in the organization knew it and connected with it?

Imagine tweeting your own life’s purpose or the values and goals of your family. Not that you need to actually get on Twitter and post these things, but the effort to zero in on a crystal clear statement on the key “Why’s” in your life potentially can lead you to unparalleled clarity and action.