Steve's predecessor knows: sometimes, stuff happens that makes you go "WTF". While Steve was reviewing some inherited PHP code, he discovered that this predecessor had built some code to handle those situations.

namespace WtfInc;

##use \Exception as Exception;

class WTFException extends \Exception
{

    public function __construct($message = null, $code = null)
    {
        if (! $message) {
            $message = "WTF!?";
        } else {
            $message = "WTF!? " . $message;
        }
        parent::__construct($message, $code);
    }
}

Now, Steve tracked down all the places it was actually used, which was not zero, but was only one location:

if ($contents === false) {
    throw new WTFException("Couldn't read the yaml");
}

This confirms what we all already knew: YAML is TRWTF.