Why limit function/method length?

• A. Long methods are better for grouping unrelated logic.
• B. Shorter methods are easier to understand, test, reuse, and maintain; aim for single responsibility.
• C. Method length has no impact on maintainability.
• D. Only the number of lines matters, not responsibility.

Answer: (B)

Shorter methods are easier to understand, test, reuse, and maintain because they keep each piece of code focused on a single responsibility. When a method does one clearly defined task, you can name it meaningfully, reason about what it does without cognitive overload, and verify it with targeted tests. Breaking complex logic into smaller methods also makes it easier to reuse parts of the code in other places without duplicating behavior, and it reduces the surface area where bugs can hide.

If a method grows long, it typically ends up handling multiple concerns in one place. That mixes responsibilities, increases cognitive load, and makes it harder to modify or test in isolation. The length of code alone isn’t the whole story, but long methods usually signal a need to refactor into smaller, clearer units. The other options aren’t good guides: long methods aren’t inherently better for grouping logic, length doesn’t have no impact on maintainability, and focusing only on line count ignores whether the method cleanly represents a single responsibility.