What are the potential pitfalls of removing slashes in PHP variables?

When removing slashes from PHP variables using the stripslashes() function, potential pitfalls include leaving the variable vulnerable to SQL injection attacks if used in database queries or compromising the security of the application by allowing malicious input to be executed. To mitigate these risks, it is important to validate and sanitize user input before processing it in the application.

$user_input = $_POST['user_input'];
$clean_input = filter_var($user_input, FILTER_SANITIZE_STRING);
$escaped_input = mysqli_real_escape_string($connection, $clean_input);