Coffee bars employ a couple of different strategies for taking and filling orders. Each strategy makes different tradeoffs.
Sometimes someone will take your order, ring you up, and then make your drink and give it to you. Other times someone will take your order, mark up a cup with the details of your order, place the cup in a queue to be picked up by a barista who will make the drink and then place it on a shelf and call it out.
That second arrangement is a kanban system, and the cup is the kanban. The cup-ban doubles as an order form that can encode most combinations that a barista should expect.
There are reasons to choose one process over another. The first method is usually applied by small or lower-volume shops with only one employee on shift. The second method is usually applied in larger, higher-volume stores with two or more workers on shift. An advantage to the store of using the kanban method is that they can take your order–and collect your money–quickly. Unfortunately for you, that often means exiting one queue so you can line up in another, more captive queue.
It’s good news for you when the barista asks you, “can I get a drink started for you?” because that should mean he has slack capacity. By the time the cashier finishes collecting your money, the drink should already be under construction. The barista shouldn’t ask you that if he already has a queue of cups to process. On the contrary, once the kanban queue starts backing up, the cashier should start stalling, even if that appears to make the cashier queue back up. The second queue has limited capacity before waiting customers start crowding each other or irritating seated customers.
Some shops get obnoxiously long lines during the morning rush. The solution to that is usually adding an additional espresso machine. The complicating factor is that the rushes don’t last, and then the surplus capacity goes unutilized for most of the day. Still, I know for certain that some shops lose sales, and even customers because of the lines, so I don’t think that strategy is employed as often as it should be.
Watch your coffee cup once your order is taken. It should never stop flowing. If it does, you should ask yourself why and imagine what you might do differently.
Curious Cat Management Improvement Blog » Management Improvement Carnival #36 | 01-Jun-08 at 11:38 am | Permalink
[...] Coffee cup kanban by Corey Ladas – “the cup is the kanban. The cup-ban doubles as an order form that can encode most combinations that a barista should expect.” [...]
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[...] Coffee Cup Kanban: Bericht über die Anwendung des Kanban-Systems bei der Bestellung eines Bechers Kaffee in einer Kaffeebar. [...]
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[...] Coffee Cup Kanban: Bericht over de toepassing van het kanban-systeem bij de bestelling van een beker koffie in een koffiebar. [...]
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Jon Strickler | 19-Jul-09 at 9:54 pm | Permalink
It is really a kanban if there is no limit on the number of cups that can be in the process at a given time? A true kanban would require that a new cup/order was not started until one was filled and left the process once this limit was reached.
Without the limit to cups in process, the cup is just another order system pushing orders into the coffee making process.
Corey Ladas | 20-Jul-09 at 2:41 pm | Permalink
Hi Jon,
I agree that most coffee shops are not strictly WIP-limited, although I’ve seen examples of some that are. Espresso drinks are still built-to-order, and there are practical limits on queue size that are imposed by counter space for the cups and waiting area for the customers. A better example of push scheduling in the coffee shop would be the baked goods or the drip coffee.
Dave Mackersie | 25-Sep-09 at 2:10 pm | Permalink
You are missing a key element that would make the process truely “lean”: Rather than just stalling customers, the cashier should switch over to helping the barista in whatever way they can whenever the queue of cups becomes too large. I don’t know exactly what that would be. It could be putting lids on, grinding coffee, adding cream, or some other task. But there should be some alternative task that the cashier switches to when the queue gets be too big. When the queue drops down again, he/she goes back to being a cashier.
Bernie Thompson | 30-Oct-09 at 10:18 am | Permalink
Dave – great point! That’s exactly right.