Looking back at my first two years as a Scrum Master, my Sprint Retrospectives were dull, boring and always followed the same format. This was a format that I had been introduced to during my time as a Product Owner, where the Scrum Master would ask the Development Team to write on post-it notes the things that they thought had gone well and the things that didn’t go so well or could be improved. These meetings often had a flat atmosphere or were a moaning session, and although actions were identified, there was no feel good factor.
I wanted this to change and was given the autonomy to do so while working as a Scrum Master at Sky Betting and Gaming. I started to look through books on retrospectives and at different websites to collate a variety of ideas. As my team were using Kanban for continuous delivery, I wanted to try and find a retrospective that would allow us to review the way that they had been working with the goal of improving their delivery process(es). I came across the Lego Flow Game.
The Lego Flow Game is a fun exercise to compare and contrast different approaches to processes with respect to how work flows. The aim of the exercise is to build different items using Lego with a defined workflow. There are set roles and in each round there are rules/processes that need to be followed. These rules/processes simulate different delivery styles – Waterfall, Scrum and Kanban. The aim of the exercise is not to identify which delivery style is best, but to get those taking part to think about the processes that they undertake and how these could be adapted in order to improve the way in which they work.
The original idea uses the Lego pieces and instructions from a Lego advent calendar. Other people had varied the exercise by using mini-figure packets. I decided that I would use some Lego Classic sets that included the pieces for Lego animals, with participants building the animals to go in a Lego Zoo.
In preparation for the session I went and bought the sets of Lego that I had identified and spent some time with my daughter building the animals to verify how long the ‘build’ process would take. This included experiments on building the Lego animals with and without instructions. In the end I decided that I would pre-bag the parts required for each animal (otherwise a lot of time may be spent looking for the required pieces) and that some basic instructions would be required.
The Lego Flow game has five required roles – Analyst, Supplier, Builder, Tester and Manager – with an optional role – the Market Representative. In my adapted version of the game, the Analyst has a selection of cards with pictures of Lego animals on them. Their job is to find a matching card for a picture of a Lego animal displayed, paperclip it to an index card and write the name of the animal on the card. This would then be passed to the Supplier as defined by the policy of the round being played.
The Supplier has access to the pre-bagged Lego pieces and basic instructions. Their job is to match a bag of pieces and instructions to the picture of the animal on the card provided by the Analyst. The card and Lego pieces are then passed to the Builder as defined by the policy of the round being played. The Builder will then build the Lego animal using the instructions provided. Once built the Lego animal, instructions and index card are passed to the Tester as defined by the policy of the round being played.
It is the job of the Tester to compare the Lego animal that has been built against the picture of the Lego animal on the index card. The animal will only pass testing and be passed to ‘done’ if it exactly matches the picture on the index card. The Manager (normally the facilitator of the session) has a stopwatch and a pen. It is their role to ensure that the policies of each round are followed and to capture metrics every 30 seconds (to create a cumulative flow diagram).
The Market Representative is an optional role and may be used if there are a lot of people in the session. The Market Representative is independent from the team and may double check the quality of items passed to ‘done’.
There are three rounds – Batch and Stage Driven (Waterfall-like), Time-Boxed (Scrum-like), Flow-Based (Kanban-like). The rules for each round are below.
Batch and Stage Driven
- This is a six minute round
- You need to build 5 Lego animals for the Lego Zoo
- All items need to be completed at each stage before they can be passed in their entirety to the next stage, i.e. the Analyst must create and complete 5 index cards before they are passed to the Supplier
- Stages are independent, with roles being a specialist skill, so workers may not help each other
- Any work that is sub-standard and rejected is stuck where it is – it is expected that all work will be done to the right level first time.
Time-Boxed
- This time there are three 2 minute time-boxes
- Before each time box, the team should plan how many Lego animals they will build (30 seconds)
- After the time-box, the team should review/retrospect how they did against the plan and what they can improve (30 seconds)
- When an item completes a stage, it can be immediately passed to the next stage – there is no need to wait for the batch to be completed
- Primary specialisms still apply, but you can now be more collaborative as a team and help each other if there is nothing to do in your stage
- Rejected items can be passed back and improved
- At the end of a time-box, partially completed work can be kept and worked on when the next time-box begins
Flow-based
- This is a six minute round
- There is no need to estimate how many Lego animals will be built
- There is a WIP limit of 1 at each stage (2 in build if there are two Builders) – this limit includes items being worked upon and those completed and ready for the next stage, i.e. when a Supplier has finished work on an item, they cannot begin work on the next item from the Analyst until the Builder has started work on the item they have just completed
- Primary specialisms still apply, but team members can help each other if there is nothing to do in your stage
- Similarly, rejected work can be passed back
During each round, metrics are captured every 30 seconds to identify how many animals are in each stage. This data can then be used to create a cumulative flow diagram (CFD) to allow analysis and discussion of the rules/processes of each round. The CFDs from running the Lego Flow game are below.
Batch and Stage Driven CFD
As you can see from the above CFD, the work built up in each stage until the work for all five animals had been completed, at which point it could be passed to the next stage. This meant that by the end of the six minute round, no Lego animals were completed (had been through all the stages).
Time-Boxed CFD
In the Time-Boxed round, it is not clear to see the time-boxes themselves from the CFD, however, there is more flow through the system, with four animals being competed by the team.
Flow Based CFD
In the Flow-Based round the flow is more evident and even, with the slope being smoother. This would probably make it easier to predict the future performance of the team.
Following the three rounds the team sat and discussed the positive and negative aspects of each and how the change in rules/processes can affect the flow of development. This then moved on to what changes could be made to the way in which the team works in order to try and improve they way in which work flowed through our system. Ultimately, this resulted in an experiment by the team to combine three elements of our process, with the goal of reducing the time it would take for that process to be completed. I will talk more about this in my next blog post.
The Lego Flow Game is a fun exercise that can be undertaken by any team to get them thinking about the way that they work and the rules/processes that they follow. It will get them to look at the problem from a different angle and hopefully they will be able to think of some innovate ways to overcome the difficulties or challenges they currently face.
The Lego Flow Game is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. Details of the original game can be found at http://availagility.co.uk/lego-flow-game/