Most of the time, we write a case study because we want the world to know that we landed an important account. It's about the name of the client and what it means that they were willing to work with us. If we made some pretty things, we of course want to show them off too. But in both cases, we're doing it to create an impression, either by name recognition or aesthetic seduction. And that's what we think sells.
You might get someone into your store by putting pretty things in the window, but if that impression doesn't hold up once they're inside, they're not going to stick around long enough to buy. Once they're inside, they need all kinds of reassurance to defeat the voice in their head telling them to hold on to their money: A trust-building connection with you. The chance to hold that thing you're selling and imagine what it might be like to own it. A good story about that thing that explains where it came from, why it's one of a kind, and how it's just as good as it looks. A promise that you'll make it right if that thing doesn't hold up.