Collaborating with the ScrumMaster
Just as a sports team requires a coach to play consistently at the highest level, so every Scrum team needs a ScrumMaster.4 The ScrumMaster supports the product owner and team, protects the team and the process, and intervenes appropriately when required to ensure that the pace of work is sustainable, that the team stays healthy and motivated, and that no technical debt is incurred.5
The product owner and ScrumMaster roles complement each other: The product owner is primarily responsible for the "what"—creating the right product. The ScrumMaster is primarily responsible for the "how"—using Scrum the right way. The two aspects are depicted in Figure 1.1. Only when the right product is created with the right process is enduring success achieved.
Figure 1.1 Doing the right thing the right way
Since the product owner and ScrumMaster roles are designed to balance each other, playing both roles is overwhelming and unsustainable. One individual should never be both ScrumMaster and product owner.