I can fit a model, but I don't know when it breaks. Now what?
You can turn the crank. Data goes in, numbers come out, and the numbers look reasonable. That is not the same as knowing what the model assumes, or when those assumptions break. Most people in this spot never test the edges. They trust the output because it ran without an error. An error message is not the same as truth. Your model can run clean and still lie to you. You are not alone with this. Your team has the same gap, even if each of you hides it differently. Use that. Stop asking who understands it best and start asking where it breaks, together.
You do not fix this by reading more theory alone. You fix it by breaking your own model on purpose, with others watching, until you see where it bends. Choose one assumption. Test it against data you know violates it. Let your team find the crack before reality does.
What changes unlock by starting
- You can name three conditions that would make your model wrong.
- Your team stops treating model output as settled fact.
- You catch a bad assumption before it reaches a decision, not after.
- You can explain the model's limits to someone outside the field, in plain words.