This article was inspired by a fantastic “What Starbucks can teach us about software scalability” blog post by Weronika Łabaj. It is a very good reading and I’m not going to repeat the things about Starbucks process. I will only do some kind of sequel by recognizing some part of that process as Lean principles.
Go ahead and read it now, I’ll wait for you here…
Have you read it? OK, now let’s find out how it correlates to the Lean principles.
What Starbucks did and why is that Lean
You probably noticed that after a payment is collected, no order is pushed to the coffee makers. Instead of this push system, a “signal” is created (an empty cup) and placed at the visible place to be picked up (pulled) by the next free coffee maker. This is nothing but Lean pull system. Among the other things, it prevents overburden (jap Muri), which is defined in Lean as one of three main reasons for a dysfunctional organization or system.
Obviously, a Starbucks wants the customer to be served as soon as possible for many reasons. You can see that they optimized their process for a short throughput time by using different “signals” (paper and plastic cups) to introduce parallel processing. The important thing here to understand that they do not optimize for a optimal resources consumption, but for a flow efficiency (“stop starting start finishing”).
Parallel processing is not the only example of taking care about flow. Take a look at their decision to “keep baristas focused on fulfilling orders instead of preventing the occasional lost coffee”. Flow efficiency over resources efficiency is also a Lean principle.
Another great example of their Lean implementation is a focus to deliver a value for the customer. Don’t forget that value is always defined from the receiver side. In our case receiver is a customer that entered a Starbucks to have a cup of coffee. Recognizing a regular customers and preparing their coffee in advance is a great value for the customer. Some would say that it’s not a big deal and it’s a practice from almost every bar, but there is a big difference here to understand. Starbucks does not rely on a barista’s good will to do so, but established a system to train baristas work in this way. It makes a big difference and shows how serious and systematic approach about value for the customer they have.
Further possible Lean improvements
Now that we recognized some Lean patterns in Starbucks process, it’s funny to play with some other process improvement possibilities derived from Lean. The first thing that comes into my mind is to limit work in progress (WIP limit). An idea is to limit the number of “work items” (cups of coffee) currently in progress. This should help to deliver faster with better quality. We could achieve this by drawing a two rows with six cup placeholders in total (three for plastic and three for paper cups). A payment collector would be required to put an empty cups into a placeholders. In case of no free placeholders, collector should stop collecting orders, and give a hand to baristas to clear the queue. Once a free placeholder appears, collector could continue with her/his primary job.
What else improvements based on Lean principles could they apply?