Karl Scotland – Using Agile to Deliver Value
Archive for July, 2010
A Pattern for Using Scrum and Kanban
Jul 27th
I’ve noticed a pattern that I’ve found myself using recently when I’ve worked with new teams that makes use of both Scrum and Kanban ideas. I’ve already said that I believe the two are complimentary, and this should help show how.
- I’ll often begin with a “Canonical Scrum” implementation. This gives a relatively simple introduction due to the ubiquitous language, standard training and often client demand. I also find that its a very good way of quickly exposing the real underlying workflow. Stressing a team by introducing a new way of working soon makes the current way of working apparent.
- After a few Sprints,once the team understands both what the desired outcome is and the current context is, I’ll ease back into what many people might call “ScrumBut”. Rather than continuing to highlight and struggle against impediments and constraints which are out of the teams control, I will apply kanban aspects to help the team acknowledge, but deal with their context without feeling dogmatic.
- Finally I’ll help both the team and the organisation improve, by seeing where the issues are, whilst continuing to be able to deliver. Sometimes the current workflow is appropriate for the team and it is smaller batches and queues that are needed. Sometimes the current workflow is a symptom of silos and poor collaboration.
So I find Scrum to be a good way of showing teams what could be possible, and finding out where I can help make improvements. Then I find Kanban a good way of enabling a smoother transition for those improvements in a way which is appropriate for the teams’ contexts.
Rally and other Announcements
Jul 20th
I have a few announcements so I thought I’d group them together into a single post.
- Firstly, I’m really excited that I’m going to be joining the Rally team in the UK. I’ve had a good couple of years with Conchango / EMC Consulting, but its time to move on, and I believe Rally are doing some great things in the Lean and Kanban space, especially with the recent acquisition of AgileZen. I’m really looking forward to working with Ryan Martens, Jean Tabaka and the rest of the Agile Coaching team.
- Next, I’m going to be at Agile2010 and will be running a workshop Exploring the Kanban Multiverse with Xavier Quesada Allue. Its an evolution of Xavier’s Visual Management workshop from last year’s conference, with some updates that have been used at XP Day London and the Orlando Scrum Gathering. I’m also going to helping out with the bag packing on the Sunday before the conference. This is a repeat of something we did last year where we applied Lean and Kanban thinking to bag packing process and learned a load and had lots of fun in the process. If you’re around the hotel, come and find us and join in!
- Finally, the LeanSSC 2010 UK conference was a success and the materials and videos can be found on the Limited WIP Society.
The Flow Experiment
Jul 16th
I put together a small simulation for the SPA Conference this year which seemed to go well, and which I re-ran at the London Limited WIP Society, and hope to run again. You can download the materials, and this is a short write-up of how it works so people can run it and experiment with it themselves.
Overview
The basic aim of the simulation is to solve maths problems. This idea was inspired by Simon Bennett and Mark Summers session The Incentive Trap which also uses maths as the problem domain. The solving of equations introduces variability into the exercise using some simple knowledge work which is hopefully more interesting and engaging than rolling dice.
The maths problems flow through the following value stream:
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Options
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Analysis
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Solve
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Check
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Accepts
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Done
The following roles are involved in the value stream:
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Analyst
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Solver
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Checker
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Accepter
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Manager
The following scenarios are used to experiment with the flow:
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Phase Driven
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Time Boxed
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Flow Based
Stages
Options
Each scenario starts with a portfolio of possible problems to solve, in the following format:
| ID | Operands | Solution |
| 1 | 3 | 25 |
In this example we have an option to create an equation with 3 operands and a solution of 25.
Analysis
When an option is selected, it is transformed into an equation during analysis. Rather than expecting participants to come up with their own equations, which could result in trivial equations, a lookup is provided. The equations in the lookup are in a different order to those in the portfolio so some effort is required!
| Operands | Solution | Equation |
| 3 | 25 | 3 * 7 + 4 |
Solve
The equations are then solved independently i.e. the solution is not available
Check
In order to check that the Solve stage produces a correct result, the equation is solved independently again.
Accept
Finally the two independent solutions are compared, along with the actual equation, to ensure it has been solved correctly
| ID | Operands | Solution | Equation |
| 1 | 3 | 25 | 3 * 7 + 4 |
Done
When the correct equation has been independently solved correctly twice, then the problem can be considered Done.
Roles
Analyst
The analyst selects the options from the portfolio, matches them against the available equations, and writes them onto index cards. Each index card should contain the option ID and the equation as follows:
Solver
The solver takes each index card with an equation on it, and solves it. Any intermediate calculations should be written on a separate sheet, and calculators should not be used (although someone who did use a calculator at SPA didn’t seem to gain any advantage!) The answer is to be written on the back of the back of the index card, to the left side, and covered with a small post-it so that is hidden and can’t be copied.
Checker
The checker also takes each index card with an equation on it, and solves it. Again, any intermediate calculations should be written on a separate sheet, and calculators should not be used. this time, the answer is to be written on the back of the back of the index card, to the right side, and again covered with a small post-it so that is hidden.
Accepter
The accepter takes the index card and confirms whether the ID and equation match correctly, and that the two answers are both the same and correct. The they are, the the problem is Done, otherwise they reject it. Each scenario will handle rejection differently.
Manager
The managers job is to keep time, ensure the process is being followed and capture metrics. Every 30 seconds they should count how many of the maths problems are in each stage of the value stream and record it on a worksheet. It is these numbers which can be fed into a spreadsheet to generate a Cumulative Flow Diagram to visualise the flow.
Scenarios
Each scenario is 5 minutes each.
Phase Driven
For a phase driven approach, the team should initially plan how many of the set of options they think that they can complete in the 5 minutes available. Then all the selected options are worked on phase by phase. Thus they are all analysed, then all handed over to be solved, then all handed over to be checked, and finally all handed over to be accepted. Any rejected work can only be moved back to the beginning once everything else has been accepted as Done.
Time Boxed
For the time boxed approach, the team should plan how many of the set of options they think that they can complete in the 1st of the 5 minutes. Those options are then worked on by the team individually. Specialism still applies, but once a problem has been analysed, it can move to be solved, check and analysed without waiting for the whole batch. At the end of the 1 minute time-box, the team should stop, review and re-plan the next minute, deciding how many problems to work on next. This is repeated until the 5 minutes are up i.e. there are 5 x 1 minutes time boxes. Any rejected work can be passed back immediately.
Flow Based
For the flow based approach, the team should pick 1 problem at a time to solve. As with the time boxed scenario, specialism still applies, so once a problem has been analysed, it can move to be solved, check and analysed. However, there should only be one problem in each stage of the value stream at a time, thus creating a pull system. Any rejected work can be passed back immediately (which may result in the WIP limits being broken), or the accepter can pull in the appropriate role to resolve the issue.
Results
The metrics from the managers worksheets can be fed into an excel spreadsheet (included in the download package) to generate CFD diagrams. Here are 3 from one of the teams at SPA.
Phase Driven
Time Boxed
Flow Based
Variations
There are a number of variations I’d like to try.
- One of the things I’ve noticed is that the maths problems may be just a little bit too difficult for some teams, and the take too long sometimes to get any really useful results. One option would be to extend the time for each scenario to 10 minutes to allow more time. I wonder whether this could make it less snappy though.
- The time-boxed scenario never really plays out how I envisaged it. This is partly down to the short time frames. Stopping, reviewing and replanning every minute doesn’t seem right – especially when you can only manage 1 problem in a minute! What i was trying to show was the small-batching nature a time-box can have. One way round this is to explicitly create the batches in a similar way to the Penny Game.
- Some people don’t like the mental exercise involved in the maths! Katherine Kirk described a variation to me where the teams used a “Pictionary” workflow instead. Options –> Describing –> Drawing –> Guessing –> Checking –> Done
- Its quite likely that the Flow scenario comes out “best” because its the last one. It would be interesting to run the scenarios in different orders to see what impact that had. Especially if there are 3 or more teams so that each team can start with a different scenario. This would possibly be more complicated to run, but with enough facilitation could be done.
Feel free to download the pack, which contains:
- Handouts – PDFs of the options, analysis and accepter worksheets for each scenario
- Spreadsheets – one with all the details used to create the worksheets, and one to be used to create the CFDs
- Powerpoint – slides with simple instructions for running the experiment
All I ask is that you let me know how you got on, and what variations you come up with. Here are the SPA results and LWS results.
Does A Kanban System Eschew Estimation?
Jul 14th
I was recently involved in a brief twitter conversation which started when Mike Sutton tweeted:
estimation is not about the number that pops out. It is about exploring effort and discovering that you don’t know stuff.
Paul Dyson responded:
spot on! This is fundamentally what I don’t like about the kanban “if people find estimation hard, don’t make them do it” mantra.
Which is where I jumped in:
where did you hear that “kanban mantra”? Not one I’m familiar with.
Only to be told:
err, it was actually in the talk you gave at mini-Spa!
Since then, Paul has blogged some more on estimation, and this is my response, hopefully clearing up what I said, or at least meant to say at mini-Spa, in addition to what I’ve already written on estimation and waste.
A simple summary and paraphrasing of Paul’s post would be:
Estimation, as part of time-box planning, leads to whole team interaction and collaboration, to create learning about past capability and forecasts of future capability
Lets start by drilling into these key points from Paul’s post. Essentially the implication is that by eschewing iteration, we cannot have whole team interaction and collaboration, cannot learn about past capability and cannot forecast future capability.
Whole team interaction and collaboration
I can think of 3 ways a team a whole team can interact and collaborate around planning a new piece of work without estimating in a time-box planning meeting:
- Cadence. The team agrees a cadence at which they will all get together to collaboratively plan new work. This planning cadence looks at what new items the team may be able to pull, given their current work-in-process, rather than estimating what items they may be able to complete.
- Workflow. The team explicitly models their workflow to make transparent that fact that they need to get together to plan new pieces of work when they are pulled. This stage could be a stage called “Planning”, or even ”Analysis”!
- Just do it! When the team pulls a new work item, they spontaneously swarm on it to plan it. This probably requires a small and high performing team.
Even so, this is assuming the whole team really does need to interact and collaborate on every piece of work. However, not every piece of work is equal, and there may be some smaller, simpler features that can be planned and delivered by a smaller group.
Create learning about past capability
We can learn about our past capability by measuring data such as cycle time, and tracking it with a Statistical Process Control chart. Common cause variation is to be expected within a stable system. However, special cause variation is something we can look at in more detail to see what we can learn (as long as we don’t change the system in response to special cause variation).
Forecast future capability
Once we understand our past (or current) capability we can use that information to forecast future capability. By understanding how long things have typically taken in the past (with natural variability) we can determine how long things will take in the future (with natural variability). Dennis Stevens has recently written some great posts discussing knowing when we will be done, using classes of service and service level agreements to manage variability.
So kanban teams do not eschew estimation simply because it is hard. Some teams choose not to estimate because they can realise the same benefits that estimation gives with a lower cost. The old joke does still apply (“Doctor, Doctor it hurts when I do this”, “Don’t do that then”). If it hurts to estimate, then find other ways to encourage whole team interaction and collaboration, learn about past capability and forecast future capability. On the other hand, if estimation doesn’t hurt, or costs too much, then it may be the right thing to do in your context.
What I think we do agree on is that when we are planning, we should decompose work for understanding, rather than sizing (thanks to Eric Willeke for this phrasing). As Mike says, the estimate is just a number that pops out of the discovery.
