About blocks, which statement is INCORRECT?

The correct choice indicating an incorrect statement about blocks is that they can only be used on screens. This is not accurate because blocks in OutSystems are designed for component reuse and can be utilized in various contexts, including actions, interfaces, and other modules, not just limited to screens.

Blocks serve as modular components which help streamline development by encapsulating logic and UI elements that can be reused across different parts of an application or even in different applications. This promotes adherence to the principles of DRY (Don't Repeat Yourself) and aids in maintaining consistency across the applications.

It's also important to note that blocks can indeed contain server actions and encapsulate client actions, making them versatile for both server-side and client-side logic. This functionality supports creating complex applications while facilitating ease of use and maintenance.