So far, we've looked at breaking work down into small chunks. We've also looked at how we can better inform the work that we carry out by shifting left the activities that we have traditionally neglected until the end of our development cycle.

Now we will apply some Lean thinking to see how we can improve the flow of work.

Just as a refresher, in Chapter 2, Agile Software Delivery Methods and How They Fit the Manifesto, we discussed the key tenets of Kanban/Lean, which are:

1. Make the work visible so that we can inspect and adapt. 
2. Break down work into similar size units, to smooth flow and reduce the "waste of unevenness."
3. Limit our work in progress so that we focus on improving our end-to-end flow.

In the following section, we talk specifically about how we enhance flow through our system, but first let's try an activity, as there is nothing quite likes a hands-on demonstration of how this works:

ACTIVITY: The coin game.
WHAT YOU'LL NEED: 10 coins, three to eight people, a timing device and a team member to operate it.
SETUP: This game is best played seated around a long table. Arrange the team around the table. Each team member should be easily able to pass coins to the next. 

This game is played in three rounds; each round, the coins will start with the first person in the line. The coins have to pass through the hands of every team member. Each coin has to be flipped one at a time before it can be considered "processed" by that team member. The round will end when the last person in the line has flipped all the coins

ROUND ONE: The batch size is 10. Give all 10 coins to the first player. They flip each coin one at a time until all 10 have been flipped and then pass the pile to the next player. The next player flips all the coins one at a time until all are flipped and then gives the pile of 10 to the next player. And so on. Start the timer when the first coin of the first player is flipped. Stop the timer when the last coin of the last player is flipped. Record the time it took.

ROUND TWO: The batch size is split. Repeat, except give the coins to the first player in two batches, one of four and one of six. Flip the coins in the batch of four first. Once the four have been flipped; pass them on to the next player. The next player then flips the stack of four coins one by one. Meanwhile, the first player flips all the coins in the bunch of six. Once they've flipped each coin, they pass the batch of six on to the second player. Again, the timer starts when the first coin is flipped by the first player and stops when the last coin is flipped by the last player. Record the time it took.

ROUND THREE: The batch size is one. For the final round, pass all the coins to the first player. Once again, they flip each coin one at a time, except as soon as they've flipped one coin they pass it to the second player. The second player can then flip the coin and pass it on to the third player. Again, the timer starts when the first coin is flipped by the first player and stops when the last player flips the last coin.

Play the game first, and then we'll discuss the possible outcomes in the results section.