The Product Goal is an integral part of the Product Backlog, providing a clear direction for the work included in it. It ensures that the team understands the primary objective they are working towards, even though not every item in the Product Backlog must directly relate to the Product Goal.
As the team completes each Increment, they make incremental progress towards achieving the Product Goal. This helps maintain focus and transparency on what is most important to achieve and why, guiding the team in prioritising their work effectively.