Method before modelDecisions that should be clear before coding
For a churn dataset, the assignment may ask for preprocessing, a baseline, two classifiers, and a recommendation. A defensible submission would define the target, keep preprocessing inside the training workflow, compare metrics on the same split, inspect class imbalance, and explain the practical meaning of false positives and false negatives.
Evaluation is meaningful only when preprocessing, validation, assumptions, and metrics fit the task. A high score by itself is not a complete academic result.