Agile Estimation Techniques
An introduction to estimation techniques and how they can help your team to understand the problem, the scope, and the effort required to deliver a solution.
Beginning a project or even a small piece of work without a clear understanding of the effort required can lead to
- missing the chance to work on something else that you could achieve with less effort
- underestimating the effort required and missing deadlines
- overestimating the effort required and eroding trust
- creating unrealistic or unreliable expectations with management or stakeholders
- poor cohesion with the rest of your organisation to bring your efforts to customers
- and more...
To get a clear picture for the effort required, your teams need to understand the problem you want to solve clearly, otherwise they can easily end up building the wrong thing which has almost domino-like consequences for the rest of your plans.
They might also understand the problem, but not understand your scope or deadlines to meet, and end up over-engineering a future-proof solution when a quick fix is all you needed for now.
This is where estimation techniques come in. They help your team to understand the problem, the scope, and the effort required to deliver a solution.
T-Shirt sizes are a simple way to estimate the effort required to deliver a piece of work. They are easy to understand and can be used by anyone in your team, regardless of their experience.
The sizes are usually represented by a small, medium, large, and extra-large t-shirt, and can be used to estimate the effort required to deliver a piece of work.
The project or product owner begins be introducing the work and explaining it as clearly as possible. They might use a whiteboard, a digital tool, or mockups to convey the idea.
The team asks clarifying questions, and can begin exploring different solutions to the problem. This might lead to what is called a "spike" to explore unknown territory to better estimate the whole work effort.
The team members indicate their estimated work as a t-shirt size, and with some luck there is quick consensus on the size of this work.
If not, then the team discusses the differences in their estimates, and the project or product owner can provide more information to help the team come to a consensus.
Fibonacci numbers are a sequence of numbers where each number is the sum of the two preceding ones, usually starting with 0 and 1. They are used in estimation to represent the effort required to deliver a piece of work.
Sometimes you'll have additional cards to indicate you don't know what to estimate, or to indicate a coffee break is needed.
The principles are similar to using T-Shirt sizes for estimation. The team discusses the work, explores possible solutions, identifies potential challenges, and gains the necessary understanding to estimate the required effort.