Golden Circle
Simon Sinek's model that communication should move from why (belief) through how to what (product), because 'people don't buy what you do, they buy why you do it'. Enormously popular as a narrative device; treat the causal claim with care - the evidence for why-led messaging outperforming is thin, and the model works best as a storytelling discipline.
Where it's used
Used in brand narratives, keynotes and internal alignment. Good for making a founder explain the belief behind the product. Do not treat it as proof that why-led ads sell more.
See it in a campaign
Apple: Here’s to the Crazy Ones (1997)
Sinek's favourite case. "Think Different" never talks about the computer. It opens with the belief, praising the misfits who change things, and leaves it to you to infer the product. That is why before what, and it reads well. Remember that Apple's comeback also needed the iMac, which is why the model's causal claim needs care.