Security | Threat Detection | Cyberattacks | DevSecOps | Compliance

For much of security history, one metric dominated: recall. Recall means: of all the sensitive data that exists, how much did you catch? If there are 100 pieces of PII in a document and your system finds 95, your recall is 95 percent. This made sense in the old security world. If a firewall missed a real threat, the company had a serious problem. If it blocked something safe, someone could investigate and fix it.

In my last post, I explained the math behind cosine similarity. Cosine similarity is a powerful search technique. When you are dealing with thousands or millions of chunks, it provides a fast, scalable way to find content conceptually similar to the user’s question. That is a major breakthrough. Without vector search, modern RAG would be much harder to build. But the mistake is pushing every retrieval problem into vector search. That is where practical retrieval starts breaking down.