In scenarios where some of your customers have a very low overall figure to be invoiced, you can exclude their pending charges from being invoice during a billing run by entering an amount into the "Minimum Invoice Amount" field in Step 3 of the billing run wizard. To reach this, go to Quick Actions -> Start Billing Run.
When the billing run takes place, each customer's pending charges will be evaluated, and if the total figure minus Tax is less than the Minimum Invoice Amount, an invoice will not be generated, and the pending charges will remain unprocessed.
The remaining charges will stay pending until there are sufficient charges of sufficient value to equal or exceed the Minimum Invoice Amount during the subsequent billing runs.
This option is particularly useful in scenarios where your payment provider requires a minimum charge per transaction, or where invoicing less than a certain amount will result in a loss due to payment provider fees.