Estimation Game - Cup of Tea

Get everyone to estimate how long it takes to make a cup of tea, and then ask them the where, who, and what questions.

What did they make?
Where were they?
Who did they make it for?

What assumptions did they make?

Recognize the similarities and differences between the answers, and consider how this might apply to your own scenario and the estimations you are about to make, or review.

The key outcome of the exercise is to create conversation amongst the team about the task, ensure it is clearly understood, and reach a shared view of the task and its size. For example, clarity over whether we have the resources readily available, how complex the task is, what the task does include, and does not include, and the options available to choose from.

Accuracy of Estimation

As we found in the Cup of Tea exercise, estimation even for simple tasks across a team can be varied and are often accompanied by assumptions based on their own experiences, knowledge and skill.

In the cup of tea exercise, given the low estimates across the group, its likely everyone assumed that they had all the resources and tools needed at hand to make tea, such as water, electricity, kettle, teabags, milk, sugar etc. Otherwise, estimates would have been higher to account for the time to go to the shop.

So, if accurate estimation is difficult even when we do know what we are doing and how we are going to do it, what should we do, when we are far from agreement on what we are doing, and far from certainty how.

Improving estimation

Agile uses a number of simple tools to help us to estimate our tasks and regularly review and refactor them based on progress and experience.

We need to be conscious that definitions and assumptions may be different, across the team, the customer, and stakeholders, all may view things differently. Agile practices and tools such as estimation games help us to reach a shared understanding across stakeholders and provide effective ways to measure, manage and monitor options and solutions.

What we anticipate to be simple and straightforward forward, maybe more complicated or complex than we first thought as we learn more about what is required and how we will progress.

Things may become more complex or chaotic due to internal or external changes causing impact.

Agile Estimation Games help us to consistently review our estimates and priorities, adjust them or revise them based on learning, gain awareness and consensus across stakeholders, and keep everyone informed.

“Conversation is key to effective communication” Agile Principle