LangGraph lets RAG systems loop, branch, and self-correct — solving real failure modes a linear pipeline can't handle, like bad retrieval going unnoticed or one-size-fits-all query handling. But it's an orchestration layer, not a guarantee of better results, and it adds real engineering overhead. This guide breaks down when graph-based orchestration is worth it for RAG, where it gets oversold, and what still matters regardless of the architecture you choose.