By default only high scoring spam will be deleted, however you can choose to deliver this email by changing the setting in your cPanel under MailScanner. Any email reported by the system as spam will have the subject line modified and header tagged to indicate them so that you can automatically filter them from your inbox and place them in a separate folder so that you can check them at a later time. You can configure MailScanner to delete or deliver email marked as Spam and/or Definitely Spam for you.