The Rule of One: the timeless copywriting principle most marketers ignore.

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Modern marketing stacks claims.

More features. More benefits. More clever words.

That’s why so much copy feels forgettable.

Great Leads reminds us of a basic rule most people have dropped: win the reader with one Big Idea in the lead.

The first 20 percent of your copy does about 80 percent of the emotional heavy lifting. If your lead doesn’t land, nothing that follows will save it.

But, What’s a Lead, Anyway?
In marketing, a lead isn’t just a headline. It’s the very beginning of your message. The first few lines or paragraphs that grab attention, set the tone, and make people want to keep reading. It’s where the sale really begins.

The Principle: The Rule of One

The strongest messages revolve around one central idea.

One core emotion.

One short story.

One controlling benefit.

One inevitable next action.

That’s how you create focus and momentum in your lead.

Veteran ad consultant James Loftus puts it simply: the more points you try to cover, the less effective each point becomes. Effective ads have one central focus.

A Short Story From the Book

Masterson and Forde analyze a Bob Bly promotion about e-books. The lift note opens with a single-sentence “story” and an inverted promise:

The sales letter then leads with one statement:

“There’s no product easier to create or sell online than a simple, straightforward instructional or how-to e-book.” 

Proof bullets and Bly’s own results support the same single idea. Clear offer. One click to act. Short. Focused. It worked because everything served the one idea.

Why This Wins

• Readers decide quickly. Your lead must persuade emotionally fast.

• When you pile on points, they compete and dilute belief. One idea concentrates attention.

• Any lead type you choose still works best when it’s anchored to one unifying Big Idea.

How To Use This Today

1. Name your One Big Idea. Complete one sentence: “The easiest way to ___ is ___.” or “The real reason ___ happens is ___.” Keep it simple.

2. Pick one core emotion to amplify. Relief. Pride. Safety. Excitement. Make your lead carry that feeling.

3. Prove one thing once. Use one stat, one case, or one vivid demo that directly supports the idea. Don’t scatter-proof.

4. Tell one tiny story in 1–2 sentences that makes the idea feel real. Then stop.

5. Ask for one action. Make the next step obvious and singular.

6. Match your lead to awareness, not trends. Use an Offer, Promise, Problem-Solution, Big Secret, Proclamation, or Story lead, but still tie everything to your one Big Idea.

The Takeaway

Don’t try to say everything. Say one thing so clearly that it becomes undeniable. Then prove it once and make the next step easy. That’s how leads work… and that’s how ads stick.

P.S. If you found this useful, please share it with a friend who might need it.