Returning null vs an If/Else Wrapper for Conditional Rendering

Returning null from a component causes a runtime error in React because null is not a valid return type for function components.

A component silently returning null hides the conditional logic inside the component itself, which is unexpected to callers and makes the render tree harder to reason about at a glance compared to handling the condition at the call site.

Components that return null cannot be wrapped in React.memo, forcing unnecessary re-renders.

Returning null instead of an empty fragment causes React to unmount and remount the component's children on every render.