Coffee shop flow

After relaying Hakan Forss’ Red Brick Cancer presentation from LKUK13 to some colleagues, we got into a discussion about ‘resource efficiency’ and ‘flow efficiency’ in reference to coffee shops.


(Names changed to protect identity)

The first company, CelestialDollars, takes each person’s order and their money, then pushes the orders through to their barista regardless of the amount of orders the barista already has.
– Order & payment: stable system (one out, one in) with WIP limit of 1
– Barista: unstable system with no WIP limit

Our second company, Expensa, takes people’s orders en masse, but limits the amount of orders hitting the barista: money is only taken for an order once the barista has capacity.
– Order: unstable system with no WIP limit
– Payment: stable system (one out, one in) with WIP limit of 1
– Barista: stable system (one out, one in) with WIP limit of 5

Finally, we have CaféFlow. It takes the order and payment customer-by-customer, limiting the amount of orders hitting the barista by only taking orders when the barista has capacity.
– Order & payment: stable system (one out, one in) with WIP limit of 1
– Barista: stable system (one out, one in) with WIP limit of 5

Does one of the above sound like your favourite coffee provider? Which one would you prefer to buy from? Which one is most favourable to the shareholders?

CelestialDollars is definitely resource efficient: they keep their coffee makers busy 100% of the time and pile orders up around the poor barista. The time it takes to deliver my coffee varies each morning, but I cannot leave as they have already taken my order and my money: I’m committed!

Expensa is better in that it limits the work flowing through their bottleneck (the barista). Unfortunately, the upstream activity fails because customers enter the process too early and have a long wait time (so again delivery is variable) – customers will normally not leave because they have ordered. Unfortunately, because orders are placed so early, they need to be repeated often by the customer before they actually get their coffee.

CafeFlow is where I want to buy my coffee. They systematically take each order and the time it takes from me placing my order to walking out the door will be relatively consistent each day; I am not entering an unknown bucket of orders or being sold false dreams of being served.

Unfortunately, because commitment is deferred until the latest moment, many companies balk at the idea of the flow efficient model: fearing that they will lose many customers because they haven’t tied them in early. Do you agree? Would you rather be tied into a process early and asked to repeat your requirements, only to receive inconsistent delivery? Or would you prefer a consistent service that gives you the option to change your mind until the last minute?

Resource efficient systems may tie in customers early but, assuming there’s an alternative, I bet they don’t have as many happy or repeat customers.

And what about your business? Are you resource efficient or flow efficient? Which do you think your customers would prefer?

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