Validation chains take seconds instead of expected sub-10ms (guards) + ~100ms (validators); overall LLM app response time degrades significantly when Guardrails enabled.

Misconfiguration causing excessive local CPU computation for ML-based validators (tens of seconds vs ms on GPU/remote), suboptimal/slow LLM choices dominating latency, synchronous execution blocking concurrency, and using large LLMs for re-validation on failures.