Why is Custom value transformation important in Laravel applications, and what problem does it solve for developers?

Why is Custom value transformation important in Laravel applications, and what problem does it solve for developers? The key reason to understand custom value transformation is that Laravel applications are usually composed of several layers that must work together predictably. Custom casts can encapsulate more specialized conversion rules when built-in casts are insufficient. 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: Eloquent attribute casting converts selected model attributes into useful PHP types or structures when models are read and written. The specific focus here is custom value transformation: Custom casts can encapsulate more specialized conversion rules when built-in casts are insufficient. 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.