You own the vector store behind a RAG product. What breaks in production that nobody warns you about?

The database part is easy. The operational problems are reindexing when the embedding model changes, recall degrading silently as filters get stricter, and memory growing faster than anyone forecast.

Grounded in researched DevOps, SRE and platform engineering interview loops, written to a senior-engineer editorial bar, and never padded to hit a word count.