Key 16 - T-Shirt Size: Michigan Agile Philosophy (MAP) Project Key

16. T-Shirt Size

I know the reality of only having three more project keys is probably starting to settle in. You’re feeling the longing already for whatever is next. I understand. It is a sad time for all of us. At least those who have been following along these last few weeks. I’ll try not to let you down as we enter the home stretch.

T-Shirt Size. I’m a Large Tall thank you. What could this possibly mean? Well, I will tell you it has very little to do with T-Shirts. It’s really about estimating the size of the project.

Before we embark on the journey that is a typical project, it is incredibly helpful if we have an idea of how big it is. Experience can be really helpful here. If you routinely build websites and a new request comes in for a website that is similar to one you have done before it’s pretty easy to estimate. If a project appears at the feet of your team that is different than anything else you have done it can be a little tricky. There are a couple ways to go about it. One way is to ask others. Yeah, that communication thing again. If you talk to people that have done something similar you can usually get an idea of the relative size of the project.

Another approach is to dissect the project into large chunks that you think are more estimable. For example if you have never built a full website before, but your team has done wireframes before you can estimate that part. The next chunk may be styling, another may be content, and finally there may be some custom development. When you break a project into chunks it is usually easier to estimate the chunks and then add them up to get a general size.

We advocate creating a project charter document of some sort. We like the Inception Deck. Some groups use A3s. Others have an Inception Document or Project Charter. All of these are great to facilitate a discussion and some group estimation.

Our T-Shirt sizing is as follows:

Small (S) = 4 - 6 Iterations, where an Iteration is 1 week. Medium (M) = 7 - 12 Iterations, where an Iteration is 1 week. Large (L) = 13 - 26 Iterations, where an Iteration is 1 week.

Note, we don’t have anything longer than 26 iterations. It’s a rule we have with our projects that none of them go longer than 6 months. Now don’t get upset…that doesn’t mean that we are killing all work on 6 months and 1 day. The idea is that we have struggled with projects that labor on and on. The 6 month rule gives us an opportunity to reassess if the project is yielding the business value we anticipated when we decided to do the work. The metaphor we use a lot is of an old farm road.

Imagine you are on this old, dirt, one lane farm road. You’re driving along and then you catch up to a slow moving tractor. You can’t pass, you’re stuck. As you look in your rear view mirror you notice cars starting to back up behind you. This is what happens when we do huge projects. The huge project (tractor) just keeps plodding along and there is no way for the smaller, faster projects to proceed. The 6 month rule allows us to assess and decide if we want to keep plodding or to pull over and let others pass. By keeping projects on the smaller size we can continue to focus on the ones that will achieve the highest business value.