Stop 07 · Agile & Product Delivery for BAsTopics · 10/10

Estimation Techniques

In short

Nobody can say exactly how long software will take. Agile teams stop pretending and estimate relative size instead: is this bigger or smaller than that one we did last month?

Techniques like Planning Poker and T-shirt sizing help a team estimate relative effort for backlog items — a BA often facilitates these sessions, ensuring the team has enough context to estimate accurately.

The purple blob holds a fan of blank playing cards next to three stacks of rotis of different heights.

Think of it like this

Rotis for a family function

How many rotis for 60 guests? Nobody counts grams of flour. Aunty says 'last Diwali we had 40 people and made 200, so this is about one and a half times that.' Comparing to something known beats guessing from scratch.

Watch it happen

Planning Poker: five votes on one story

1/5The BA reads the story. Everyone picks a card in secret, then all reveal at once.

The big ideas

What you need to know

Relative, not hours

Story points compare effort and uncertainty to other stories. A 6 isn't a fixed number of hours.

T-shirt sizes

S, M, L, XL works well for rough, early sizing of big items before they're split.

Planning Poker

Secret votes stop people anchoring on the first number said. Big gaps reveal hidden knowledge.

Velocity

How many points a team usually finishes per sprint. Use it to plan, never to compare teams.

Save yourself the pain

Common mistakes

Oops

Turning story points into hours to report to management.

Do this instead

Use velocity to forecast in sprints. Points are for the team's planning, not a timesheet.

Oops

The BA estimating stories on the team's behalf.

Do this instead

The people doing the work estimate. The BA explains the story and answers questions.

Your mission

Size your week

~20 min

Quick check

In Planning Poker, three people vote 3 and one votes 13. What should happen next?

Go deeper

1Practice Planning Poker-style estimation with a small group on hypothetical stories.
2Learn why relative sizing (story points) tends to be more accurate than absolute time estimates.
3Understand a BA's role is providing clarity so estimates are informed, not just facilitating the exercise.