Glossary
Secrets Management
Secrets management answers 'how is this API key, password, or private key stored and handed out safely' — encrypted at rest, distributed over a secure channel, rotated on a schedule. It does not answer 'who is allowed to use it and for what,' which is the separate job of authorization. A vault that stores secrets perfectly still leaves open the question of what happens once a service has successfully retrieved one.
The two disciplines are often bundled into the same product, which makes it easy to assume that solving one solves the other. A secret retrieved safely from a well-run vault can still be used far beyond what its retriever's task required, if nothing downstream of the vault checks that.