Why is it important to pay attention to syntax errors and unexpected variables in PHP coding?

Syntax errors and unexpected variables can cause your PHP code to not run properly or even break entirely. It is important to pay attention to these issues because they can lead to bugs, security vulnerabilities, and unexpected behavior in your application. By carefully checking for syntax errors and properly handling unexpected variables, you can ensure that your code runs smoothly and efficiently.

// Example of handling unexpected variables
$variable = isset($_POST['variable']) ? $_POST['variable'] : 'default_value';