How can WordPress plugins affect the functionality of PHP includes in different files on the same server?

WordPress plugins can affect the functionality of PHP includes in different files on the same server by potentially conflicting with the file paths or overriding functions used in includes. To solve this issue, it's important to properly enqueue scripts and styles in WordPress plugins to prevent conflicts and ensure that includes are properly referenced using WordPress functions like `plugin_dir_path()`.

// Example of properly including a file in a WordPress plugin
include plugin_dir_path( __FILE__ ) . 'includes/my-file.php';