A case study is a documented account of a client's problem, what you did, and the measurable result. Its purpose is proof, not promotion. The strongest case studies quantify the outcome and describe a situation the prospective buyer recognizes as their own.

A case study that describes what you delivered is a brochure. One that describes what changed is proof. The number matters more than the narrative, and the resemblance matters more than the number. A buyer needs to see their own situation, not your capabilities.

Example:

Not: we ran a comprehensive campaign. Instead: this firm was stuck at a level for two years and, within a defined period, reached a specific measurable outcome.

What makes a case study persuasive?

A measurable result, and a starting situation the reader recognizes as similar to their own. Without both, it reads as promotion rather than proof.

Why do most case studies fail to convert?

They describe the work performed rather than the change produced. Buyers care what changed for the client, not what tasks were completed.