At what point does it become beneficial to implement a template system in PHP development, considering factors like site size and design changes?

Implementing a template system in PHP development becomes beneficial when the site size grows larger and there are frequent design changes needed. This helps in separating the presentation layer from the business logic, making it easier to manage and update the design without affecting the underlying code.

<?php
// Template file example
$template = 'template.php';

// Include the template file
include $template;
?>