What Are Acceptance Criteria?
Acceptance Criteria represent conditions of satisfaction. They are a set of statements indicating the conditions that must be met in order for a Story to be completely realized.
So what does this mean, exactly? Here's an example:
User Story: As a home owner, I need to have windows in my house so that I can see what's outside and enjoy sunlight and fresh air while inside.
- Window sills must be exactly 3.5 feet from the floor.
- Windows must have 9-mullion panes.
- Windows must have swivel locks on the inside.
- Window sashes must be tiltable for easy cleaning of inside and outside.
- Windows must have removable and slidable metal screens.
- Windows must have removable and slidable storm sashes.
- Home owner and family must be able to slide window sashes easily up and down.
You can probably think of some more acceptance criteria that should go along with the windows in this house. Should they have shutters?
The important thing to notice about these criteria is this: Each of statement leads to a clear pass or fail. This is critical, or your acceptance criteria will result in confusion. There can be no partial acceptance: Either the criterion is met or it is not.
Acceptance Criteria need to address both functional (what the user actually uses and experiences) and non-functional (the user is not aware of these, but they are critical for the success of the Story–for example meeting security or page-load requirements)
Stories are incomplete without Acceptance Criteria.