Which of the following is NOT a reason a payment might be late?

Payment processing automation is not a reason for a payment to be late because automation typically streamlines the payment process. When systems are automated, they reduce the possibility of delays that might arise from manual processing, such as human error or oversight. Automation helps ensure that payments are initiated, processed, and sent out in a timely manner, as systems can operate efficiently without the same constraints that manual processes face.

In contrast, the other options highlight situations where delays can occur: if a payment approver is unavailable, that can lead to waiting times for authorization; missing a cut-off deadline can result in payments needing to wait for the next processing cycle; and human error, such as incorrect data entry or miscommunication, can also cause delays in payment completion. Therefore, the presence of automation typically enhances efficiency and reduces the likelihood of late payments, making it an inappropriate choice for a reason behind delays.