The central thesis
The model can be correct. The system can still fail.
For a long time, I followed the standard recipe: more data, larger models, better metrics. Real systems challenged that belief.
The root cause is often not the loss function, the optimizer, or the architecture. It is hidden state, implicit dependencies, untracked changes, weak observability, and timing effects.
That is why I treat decision-making as a systems problem, not only as a model problem. I care more about understanding failure modes than showcasing demos.
Determinism is not a property of the model alone. It is a property of the surrounding system design.