A demo is a story. Production is a stress test. I’ve seen AI apps that feel like magic on a laptop… then crash the moment 10 users show up. Why? Latency kills the experience LLM outputs become unpredictable at scale No fallback when the API rate limits hit Prompt engineering works once, not for every edge case I learned this the hard way: Reliability > cleverness. If your AI stops working at 2 AM on a Sunday… users don’t care how good the demo was. Build for chaos, not for applause.