Why we publish case studies
Two reasons. First, you should be able to see the work before you sign anything — not just a portfolio of screenshots, but the actual reasoning behind why a particular stack was chosen, what trade-offs were made, and what shipped.
Second, the case studies are documentation for future clients. When a prospect asks "can you do X for us?" the answer should be "yes, here's a similar engagement and what it took" — not a generic capability statement. Every case study is meant to do that work.