Your question is Diagnosing Long-Running Jobs. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
An existing job that was running smoothly suddenly ran for a longer time. How do you analyze the issue that caused the long running time? Explain a practical, step-by-step diagnostic approach that distinguishes data, code, infrastructure, dependency, and scheduling causes. State which operational data you would inspect and how you would validate the root cause.