Why is Rules method important in Laravel applications, and what problem does it solve for developers?

Why is Rules method important in Laravel applications, and what problem does it solve for developers? The key reason to understand rules method is that Laravel applications are usually composed of several layers that must work together predictably. The rules method defines the validation constraints for incoming fields. Ignoring that boundary can lead to duplicated logic, poor security, unnecessary database work, or code that is difficult to test. Why it matters in practice: Form Request classes encapsulate validation rules and authorization checks for a specific incoming request workflow. The specific focus here is rules method: The rules method defines the validation constraints for incoming fields. This question is designed to test not only terminology, but also how the concept fits into Laravel's request, application, database, security, or deployment workflow.