Sprint Planning Pt. 1: Stop with the Points Already

"Our culture thrives on black-and-white narratives, clearly defined emotions, easy endings, and so, this thrust into complexity exhausts." --Caroline Knapp

I've been doing a lot of reading and thinking about story points lately, and over time I have been edging toward what I now see as a necessary conclusion. Story points are meaningless. Even... Wait for it... POINTless. Yes, I just did that.

To recap, when planning a development sprint, it's customary to assign a user story a point value as a measure of... Well, to be honest, I really can't tell you what it's measuring. I can recap what people say about what it's measuring, however I've become skeptical of whether or not points are measuring what people think they are. And even moreso of whether or not it's a good use of time to do so.

Definition of a "Point"

Here's the root of my problem with story points. What are they and what do they measure? These aren't simple questions, either. If you read here, you get the idea that points are a measure of complexity. However, this StackExchange answer tells the reader that points need to be a measure of size, not complexity. Both will tell you that points are not a measure of time, but everywhere I've run into the practice, someone has always defined a point something along the lines of "What one developer can do in one day". Which certainly implies that points are used to give some measure of time. So I have a hard time getting started here, because I don't even know what I'm supposed to be measuring. Time? Size? Complexity? The amount of effort it takes for two women to have one baby? 

What's the Point, anyway?

I promise- I'll stop doing that now. Maybe talking through why we need points, we can come to an agreement on what they are. We need them for estimating, right? But estimating what? The amount you can do in a two week sprint? The amount of time you need to finish a certain set of features in a product? After all, you assign points, add them up, and divide by about what your velocity has been, right? Because that works.

Except, of course, it doesn't. Addressing the latter poi ISSUE ::ahem:: first, we all know that doesn't work. Regardless of what some may say, points do not mean you don't need to re-estimate. Software development is a process that builds on itself with every build adding to the whole an impacting the effort/size/complexity/time needed for future changes. I'd be very dubious of the point value of any story not going into the next sprint. I'd be even more dubious of any time estimates derived from arithmetic on points, velocity, and time.

So, maybe it's a good way of determining what can be worked on in the coming sprint. Problem is, without definitive answers to the question "What does a point measure", using points to determine what stories can fit into a sprint is a terribly uncertain process.

If we take the definition of points being a measure of the size of the story, then we truly have no idea how long a story will take. In fact, the StackExchange user in the link I referenced illustrated this very thing. He gave examples of the complexity of a 5-point sized story varying by a number of factors, leading to wildly different completion times. I don't really see that as a practical way to plan a sprint. More importantly, I don't think the people who expect me to plan sprints will see that as a practical way of planning sprints.

If we take the definition of points measuring complexity, we run into a different problem. How do you measure "complexity"? It's not like defining the length of a metre or defining a joule. the only way is to compare the complexity of one thing to the complexity of other things until you get something that feels like a match. Inaccurate, sure. But that's why it's called "estimating" and not "precision". I'd be basically okay with this except for a couple of things:

1. That which is complex to one developer may not be to another. Planning Poker is supposed to account for this, but it doesn't. In fact, it ironically exacerbates the problem it claims to solve. My 5 point complexity story may be another's 2 point complexity. To assign it 5 or 2, then, is meaningless outside the context of the developer who will be working on it. And splitting the difference to make it 3 or 4 is just compounding the uncertainty of an already uncertain process.
2. Complexity has nothing to do with the amount of time it takes to do the task. Planning Poker assumes that every developer handles every type of complexity in the same way and at the same pace. Maybe one guy tackles a complex story by diving in and coding until he grinds to a solution. Maybe another takes time to read more on the subject, asking questions, and only starting when he feels he has a better understanding of the subject. Given this, complexity can only correlate with time if every developer approaches complexity the same way.

Either way you look at it, you're trying to objectively quantify a series of subjective data points. Logic 101 tells us that this is a highly inaccurate way of measuring anything.

Velocity

Finally, we get to Velocity, which I'm pretty sure is the whole reason we bother to keep track of points in the first place. Velocity is nothing more than the sum of the points of the stories in a given sprint. It purports to measure the amount of work done in a sprint so you can compare to other sprints and then plan a timeline for future features.

Where to start.

First off, all this gives you is a comparison of how you've been objectively quantifying the subjective sprint over sprint. But as a comparison of the actual work done? All you're doing is comparing arbitrary numbers to arbitrary numbers and pretending it's a meaningful measure of productivity.

Secondly, using this as a future planning tool is a recipe for disaster. In order to make that work, you'd have to give point estimates to everything in your backlog and then continually refine those estimates in light of what the previous sprints have accomplished. Do that for long enough, and sure. your velocity will become a more and more accurate tool for predicting the amount of work the team can handle. But at what cost? At what time commitment?

Conclusion (WHEW!)

I'm not saying we need to stop estimating anything. Projects, stories, releases, versions, whatever unit of work that is needed, all need to come with some idea of what it takes to accomplish them. What I am saying is that we need to re-think the whole point estimation bit and ask ourselves if this isn't just an overly complicated process. Effort, complexity, productivity- these are all complex issues that are impossible to quantify in a simple context. Maybe we need to stop trying. Because I really hate unnecessary complexity. I'm not even much of a fan of necessary complexity. I'm lazy and don't want to work any harder than I have to in order to solve problems.

Next article, what I see as the real root of the problem and what I have started doing about it.