Overview

• What you’ll learn: What Product Backlog Items (PBIs) are, the User Story format, INVEST criteria, acceptance criteria, and common anti-patterns in story writing.
• Prerequisites: Lesson 26 — The Product Goal.
• Estimated reading time: 14 minutes

Introduction

The Scrum Guide does not mandate User Stories. PBIs can take any form — user stories, tasks, bugs, spikes, or plain descriptions. However, User Stories have become the dominant format because they focus on the user’s perspective and the value delivered.

The User Story Format

As a [type of user], I want [some capability] so that [some benefit].

The “so that” clause is the most important and most commonly omitted part. Without it, you know what to build but not why.

INVEST Criteria

Good PBIs follow the INVEST model:

Acceptance Criteria

Acceptance criteria define when a PBI is “done” from a functional perspective. They are specific, testable conditions that must be met. Format: Given [context], When [action], Then [expected result].

Common Anti-Patterns

• “As a developer, I want to refactor the database…” — This is a task, not a user story. Who benefits?
• Missing “so that” — You know what to build but not why. The PO cannot order by value without the “why.”
• Epic disguised as a story — “As a user, I want a complete CRM system.” That is not a story; that is a product.
• No acceptance criteria — How do you know when it is done?

Key Takeaways

• PBIs can take any format, but User Stories focus on user value.
• The “so that” clause explains why the feature matters — do not skip it.
• INVEST criteria help assess PBI quality: Independent, Negotiable, Valuable, Estimable, Small, Testable.
• Acceptance criteria define “done” from a functional perspective using Given/When/Then.
• Avoid anti-patterns: technical stories, missing “so that,” epics as stories, no acceptance criteria.

What’s Next

In Lesson 28, you will explore the Sprint Backlog — the Developers’ plan for the Sprint.