What potential pitfalls should be avoided when constructing links to subsequent pages in PHP applications?

When constructing links to subsequent pages in PHP applications, it is important to avoid hardcoding URLs as this can lead to broken links if the URL structure changes. Instead, it is recommended to use PHP's built-in functions like `$_SERVER['PHP_SELF']` or `$_SERVER['REQUEST_URI']` to dynamically generate URLs. This ensures that the links will always point to the correct pages even if the URL structure changes.

<a href="<?php echo $_SERVER['PHP_SELF']; ?>">Next Page</a>