Security cards can be used in case the products you manufacture are lost.
For instance, let’s assume that you manufacture locks. Your customer purchased the locks you manufactured, and they later lost the key and even the spare keys. What are they supposed to do now? How will they have their new keys manufactured?
Security cards come into play at this point. When your customer brings the lock and the accompanying security card to you, you can easily manufacture the key that was earlier introduced to the system via that card, so that you guarantee the security of your customer.