Beyond the Playground: Four Critical Failure Vectors in Production LLM Systems

Production LLM systems fail in predictable, structural ways that testing environments mask. This article exposes four failure vectors—input distribution shifts, context contamination in multi-turn systems, undocumented model behavior changes, and adversarial user creativity—that cause prompts to break silently when deployed. Understanding these vectors is critical for shipping robust LLM features that survive real-world usage.