I walked into the Chantilly branch this morning to make two cash deposits. There were two tellers working, only one window open. I waited in line, as I was the next customer, at which I was greeted by the teller. The teller was processing my first transaction, and noticed that I had change for the second deposit, and asked that I use the coin counter. As I walked over to the coin counter, another customer approached the teller that was closed, and was waiting for me to finish. When I finished using the coin counter and walked back to the counter, the teller had completed my first transaction, and was working on the second transaction, which was for approximately 1,500.00. I noticed I was short on the coins and quickly ran out to my car to get the difference. When I arrived back, the customer in line was being processed, as my 1,500.00 sat on desk.Perturbed, as this was not my first negative experience, I was shocked that the teller took the customer, who was not waiting in the right area, as my cash laid in front of her. Furthermore, the teller stopped counting my deposit, which inconvenienced me, processed the other customer, and then started over to complete my second deposit.Clearly, further training is needed at this bank. When a customer arrives and has multiple deposits, the teller should complete all transactions prior to taking another customer in line. The distance between the teller and my car was about 100 feet. It took me all of 30 seconds to get the difference in the deposit from my car.Very dissatisfied with this bank.