Breaking Down Big Stories: Why and How to Split Product Backlog Items
Large product backlog items slow teams. Learn direct methods to split them into smaller, valuable pieces for faster delivery and better feedback.
Teams often face product backlog items that feel too big. They are hard to estimate, hard to start, and even harder to finish within a Sprint. These large items, sometimes called 'epics' or 'themes', are not inherently bad. But they must be broken down before they can become Sprint Backlog items. This is not just about making them fit. It is about enabling empiricism and delivering value sooner.
Why Smaller is Better
The Scrum Guide states that Product Backlog items that can be Done by the Developers within one Sprint are generally deemed appropriate for selection in a Sprint. A large item often means a long cycle time. This delays feedback, increases risk, and makes adaptation difficult. Smaller items allow for quicker completion, faster learning, and more frequent delivery of value. They also simplify planning and make progress more transparent.
When to Split
Splitting is a key part of Product Backlog Refinement. This is an ongoing activity, not a one time event. The Product Owner and Developers collaborate to refine items, adding detail, estimates, and order. As items near the top of the Product Backlog, they should be small enough to fit comfortably into a Sprint. This means splitting happens continuously, well before a Sprint Planning event.
Techniques for Splitting
There are several practical ways to break down large items. The goal is always to maintain value and ensure each new item is independently deliverable and testable. Think of splitting along different dimensions, not just by technical layers.
- By workflow steps: A complex process can be split into individual steps. For example, 'Process customer order' could become 'Submit order', 'Process payment', 'Confirm order'.
- By business rules: If an item has multiple conditions or rules, split it by each rule. 'Apply discounts' could be 'Apply loyalty discount', 'Apply seasonal discount'.
- By user type: Different users might interact with a feature differently. 'Manage user profiles' could be 'Admin manages profiles', 'User updates own profile'.
- By data variations: Handle different data inputs or outputs separately. 'Generate report' could be 'Generate basic report', 'Generate detailed report with filtering'.
- By operational boundaries: Split along natural boundaries in the system or organization. For example, an integration with a third party system could be split by the specific API calls or data exchanges.
The Art of Vertical Slicing
Resist the urge to split horizontally. Horizontal splitting means separating an item into technical layers like 'database changes', 'API development', and 'UI work'. This creates dependencies and delays value. Instead, aim for vertical slices. A vertical slice delivers a small, end to end piece of functionality that provides value to the user or system, even if it is a very basic version. Each slice should be potentially releasable.
Maintaining Value and Definition of Done
When splitting, ensure each new, smaller item still represents a complete increment of value. It should be understandable on its own and contribute to a larger goal. The Definition of Done applies to these smaller items. Each split item must be capable of reaching a Done state within a Sprint. This commitment to 'Done' ensures quality and prevents accumulation of incomplete work.