How can developers refactor their PHP scripts to improve code organization and avoid issues with included files?

Developers can refactor their PHP scripts by organizing code into separate files based on functionality or purpose. This can help improve code organization and make it easier to locate and manage specific sections of code. To avoid issues with included files, developers should use relative paths when including files to ensure that the files are properly included regardless of the file's location in the project directory.

// Example of including files using relative paths
include_once(__DIR__ . '/includes/functions.php');
include_once(__DIR__ . '/includes/database.php');