In the intended PAM/libpam-script configuration, in the case of the script running SSH to start a second instance as root, in the case the second instance (running as root) fails and returns an error exit code, libpam-script will report failure to the PAM stack, causing the authentication to fail, thus the SSH login to fail, and the ssh command that was launched in the first instance of the script, resulting finally in the first instance of the script to also fail, the first instance of libpam-script, and thus the first PAM stack. Setting cfg_verbose=1 will cause the script's verbose output to appear on screen in cases where a service invoking the PAM stack allows, e.g. when running the 'su' command.