The credit card is then authorized to verify that they do have funds available. Afterwards they are connected to your operators or your prerecorded content. Preauthorizing the funds prevents a situation where they receive the benefit of your services but don't pay for them because their credit card is no good. The 800 bill to credit card service provides a way for both you and your client to be comfortable with your phone business. They get access to the product they purchase and you get the money you worked hard to earn.