The 7 Bullshit Agile Estimation Problems

Estimating stories for an upcoming project is one of the more difficult tasks that agile teams have to perform. It’s never easy to determine how difficult it will be to implement a particular feature, especially when you’ve got different personalities, goals, and levels or experience in the same room. Unfortunately this all leads to people coming up with excuses and roadblocks which lead to inaccurate estimates.

I’ve identified seven problems pitfalls of the agile estimation process that I’m sure many other teams have experienced:

1) Estimating Time Rather Than Complexity

The point of estimating stories with planning poker cards is that you estimate based on the story’s complexity, not on how long it will take you to complete the actual feature. A story that’s an 8 is more complex than one that’s a 5, but it doesn’t meant that the 8 will take two days. It could take an hour or a week, it’s all relative.

Why it’s Bullshit
Estimates based on time make planning commitments difficult and velocities unreliable.

2) Not Estimating For “Simplest Possible Solution”

The “Simplest Possible Solution” is just that, what’s the simplest way that the feature described in the story can be implemented. When you get away from this you start going down all sorts of “what if” roads that always end up bumping up your estimate.

Why it’s Bullshit
Trying to guess what the product owner will want or what the completed feature entails is a waste of time.

3) I’ve Never Done That Before

There aren’t many software problems that haven’t been solved. Most of them are things that have been solved a thousand times in a hundred different ways. Adding complexity to a story because you’ve personally never solved that problem is shortsighted.

Why it’s Bullshit
Just because you’ve never done something doesn’t mean it’s complex. Lean on your team or network of developer peers to help solve these problems.

4) Estimating Stories In Excessive or No Isolation

Stories should be estimated in isolation, just as they should be written so as not to depend heavily on one another. However, developers will often try to assign too much complexity to a story because of assumed tasks or features that they think would accompany the story in a completed state. For example:

As a user I should be able to login
As a user I should be able to upload a profile photo
As a user I should be able to change my address

Some developers will see the first story and immediately think of the complexity of creating a user model, the controllers and views that go along with the entire registration process.

Alternatively some developers will see the last story and think “Oh I just need a form field for the e-mail address when the user is editing their profile.”

Why it’s Bullshit
The first extreme gives you chunks of related stories with too much padding that are never as complex individually as they are as a whole. The latter only (sometimes) works when the actual stories are extracted out into a bunch of very small stories, which has its own set of problems.

5) Gaming Velocities

If you’re looking to “guesstimate” how long a project will take to complete, you could grab some story cards and pick out what you think might be a week of work. If you add up the points assigned to those stories you’d have an estimated velocity. However, if you’ve padded your stories, or purposefully pick out a small number of stories, your project is going to appear much lengthier than it really is.

Why it’s Bullshit
You don’t look any better completing 50 points per iteration when you padded the hell out of your estimates than you do when you do 20 points per iteration with accurate estimates.

6) Always Assume The Worst!

There seems to be this mantra with some developers, “Always assume the worst!” When you come across a slightly vague story, let your imagination run wild and assume that the product owner is going to want the most complex solution possible.

Why it’s Bullshit
Remember, every story is a negotiation. You’re not going to know the exact details of the story until you have your planning meeting with the product owner. Often times the product owner would never have been able to dream up the solution on which you based your estimate.

7) Padding Padding Padding

Padding is all Bullshit
The problem of padding estimates creeps into nearly all of the above six issues. It introduces bad data early in the life of the project and makes every other step of the process unreliable. It’s almost always in an effort to cover one’s ass but it’s painfully transparent and reeks of amateurism.

Don’t pad your estimates.

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