Handle the line
The line moves, and nobody is remaking drinks.
Where it goes wrong
One cashier is the whole counter at the busiest hour, so the line waits on one person’s hands and ears.
What changes
Guests order themselves at the kiosk and get a number, and your staff see each order on a phone or tablet at the counter.
What does it
Friday, 6 pm
One evening, step by step
Six in the line, two of them still reading the board.
The kiosk takes three of them while your cashier takes cash from the fourth.
Each of them leaves with an order number, and the sugar was tapped, not shouted.