Bill Bernbach's most repeated lesson: find one true thing about the product, and say it with everything you have. The VW 'Think Small' campaign succeeded not because it was creative — it was ruthlessly focused. Every element (the tiny car on a white page, the self-deprecating copy, the honest admission of ugliness) served a single idea: honest, confident smallness.

Campaigns fail when they try to say multiple things. Great campaigns say one thing, unforgettably.

Bernbach believed consumers were not idiots. He famously wrote: 'Nobody counts the number of ads you run; they just remember the impression you make.'

Great advertising respects that the consumer can complete the thought. It doesn't explain the joke. It doesn't show the happy ending. It sets up a tension and trusts the viewer to resolve it. This is why Bernbach's ads for Volkswagen, Avis, and DDB's work for Alka-Seltzer still feel sophisticated 60 years later.

Jean-Marie Dru's disruption methodology starts with a deceptively simple question: what is the convention in this category, and what would happen if we did the opposite?

Apple's '1984' followed this principle. Every computer company was communicating logic, specs, and productivity. Apple communicated emotion, rebellion, and identity. They didn't enter the category — they redefined it.

Dru's framework: 1. Map the category conventions explicitly 2. Identify the convention that most contradicts where the consumer is going 3. Find the disruption — the break with that convention 4. Build the vision — the brand the disruption serves

Mary Wells Lawrence built brands that people wanted to belong to, not just products people wanted to own. Her campaigns for Braniff Airlines ('The End of the Plain Plane'), Alka-Seltzer, and Love's cosmetics created entire worlds — mythologies with characters, rituals, and emotional stakes.

Great campaigns don't just sell products. They create identity. The consumer who buys isn't just solving a problem — they're joining something. Wells understood this 40 years before 'brand community' entered the marketing lexicon.

Ogilvy distrusted advertising that asserted without evidence. 'The best, the finest, the most' — these claims are noise. Specific, verifiable, unexpected facts are signal.

His research showed that specific numbers outperform round numbers ('reduces wrinkles by 47%' beats 'reduces wrinkles dramatically'). Named sources outperform unnamed sources. Demonstrations outperform descriptions.

Great campaigns find the specific, verifiable thing that competitors can't or won't say — and say it loudly.

The worst thing that can happen to a great campaign idea is the client changing it after one quarter. The second-worst thing is the agency changing it.

The campaigns that built the strongest brands — Marlboro Man (20+ years), Absolut bottles (25 years), Dove Real Beauty (20+ years) — were built on absolute consistency of idea executed with infinite variety of expression. The idea stayed constant. The executions evolved.

Great advertising is a long game played with a consistent hand.