All PBIs completed by the team should be “potentially shippable” increments of complete value. In order to do this, they must touch all the layers and components of the product so that the functionality produced is truly complete, not just a prototype… a “slice” through the system. In other words, all of the work that is required for shipping product needs to be completed on all individual PBIs. Creating slices through our system allows the Scrum team to deliver value each and every Sprint and also allows for the Product Owner to change direction to a new feature if it is more valuable for a future Sprint. What happens if we don’t create and complete PBIs that are slices through the system? We risk falling into a pattern of not having a potentially shippable product each Sprint, and, even worse, we may regress into a waterfall type process that produces nothing of value to the customer until the end of the project.