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

Why is Conditional validation important in Laravel applications, and what problem does it solve for developers? The key reason to understand conditional validation is that Laravel applications are usually composed of several layers that must work together predictably. Validation can change based on other input values or business conditions. 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: Laravel validation provides declarative rules for checking incoming request data before application logic persists or processes it. The specific focus here is conditional validation: Validation can change based on other input values or business conditions. 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.