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In the previous post about the Kan Bun bakery we saw how to use Kanban boards for visualization. We learned about work in progress and how the orders are gradually completed over the individual steps.

Up to now, Betty the Baker completed the orders one by one, as quickly as she possibly could. However, customers being customers, they say and things like “When can I expect my delivery, I need it!” “How long does it take?“.

So in this blog post we are going to follow the breadcrumbs towards a planning method for our Kan Bun Bakery. We’ll figure out where to start, how to identify the goal, and then walk in a general direction from start to the finish line.

Fun fact, questions about the When/How long/How much? are exactly what managers are paid to ask. Apparently managers are in some kind of internal customer role…but that’s brain food for another day and blog post.

Where do we start and what can we build upon?

It’s a good thing we don’t have to start from scratch here! Customer orders arrive weekly on Monday, every week. This is a stable rhythm, we call this our iteration. Therefore, we say our iteration length in this example is “1 week”.

Every Monday, at the start of our iteration, we can also count the orders. Therefore, we can say our iteration backlog is “X amount of orders”. Per week of course!

Another thing we can build upon is the baker’s meeting structure. As most good managers do, she does a daily “How are you doing?” with her shop assistant. Every week she checks the orders for the coming week, planning the sequence of jobs. In the course of this weekly meeting, Betty also does a quick recap with her assistant of what went well during the last week, aiming to identify ways to improve their daily operations.

We also know that several roles are involved in this baking scenario. Of course there is the role customer. Betty has two roles, she is a small business owner and also does all the baking of the delicious and healthy bread. Planning is also in the responsibility of her role, we summarize all her roles under “baker“.

So what’s missing?

To answer the customers’ questions about the “how long?” we need two more ingredients: How much is there to do? and How fast do we go?
Because we know our starting point, we could then figure out how long it will take to get there.

How much? Effort Estimation

Betty The Baker has a lot of professional experience, so she can tell intuitively how long it takes to prepare the dough for the different recipes. That’s our effort, it is “the amount of work we have to put in”. However, for the sake of the argument, the effort for all kinds of bread in this example will be 1 hour.

So when our iteration backlog for the week is “X amount of orders” (remember?), each order with an effort of 1 hour, the total effort per week is (X amount times 1 hour) = (X hours). There we have it, this is how much we need to do.

How fast? What is our Capacity?

To get a grip on the “How fast?” part of the question, we’d need some kind of baking speed. You might have noticed that there are all kinds of speed in our daily lives, and they usually contain the preposition “per”. Kilometers per Hour. Meters per Second. Breads per Hour. Breads per Week. I sense a pattern there…

Wait, “Breads per Week”? That one we know! Betty works 40 hours per week. With each bread being estimated to have an effort of 1 hour, our baking speed is 40 Breads per Week. Now we know how fast we go, that’s our capacity!

How long?

Now that we managed to figure out the How much? and How fast?, the next part is surprisingly easy, all we have to do is to combine both.

Let’s see how that goes!

Your order is the 23^rd in line. How long will you have to wait until 23 breads are ready and you can pick up your order?

(23 Breads) divided by (40 Breads / Week) ≈ 0.57 Weeks. So how long? Wednesday afternoon!