These are some of the benefits of working with a product team over a project team:

• Better quality: Project teams are often under pressure to deliver on budget or on time; this is how they are usually managed. If the project comes under pressure in terms of either of these, the scramble to complete it will result in a lower-quality product. If integrating with other systems, this can lead to high dependency (tightly-coupled reusability) or total autonomy (no reusability, which will probably involve us reinventing the wheel several times) rather than the sweet spot of getting just the right level of coupling and reuse. 
• A sense of ownership: There is a sense of ownership that comes built-in with product teams; they've been responsible for their product from concept to delivery. Project teams know they will be moving on to the next project, and although they will try to their best as professionals, they will have little opportunity to provide a sense of ownership and responsibility once they've transferred to their next project.
  A software development team responsible for maintaining its product and keeping the lights on in the production environment will do all they can to minimize the effort they have to put into that, usually by automating repetitive tasks so they can put their energy into developing product features. 
• A learning mindset: Shifting right to realize value sooner isn't just about moving from predictive to adaptive planning, but this does help. Building a complex system requires both a learning process and time for us to get things right, as we discussed in Chapter 1, The Software Industry and the Agile Manifesto. Even Winston Royce back in the 1970s was saying that we need to develop software iteratively/incrementally so that we can learn and improve. We learn as we go, and by making the product team long-lived, for the life of the product, we keep the learning within the team.

In a nutshell, this helps us start to develop what is known as business agility—that is, our agility moves beyond just our software teams themselves and begins to permeate through our business. Often, beginning with our product management team and through the use of data, insights, and measurements, we start to become a learning organization.  

At the beginning of our journey towards business agility, we recognize that our business and the software that supports it are inextricably interlinked. Being able to adapt our software rapidly will help our ever-evolving business keep doing just that, allowing our company to keep up with change and maintain its competitive edge. The only constant is change, and with technology advances accelerating on an exponential curve (Moore's Law and then quantum computing) we need our business to be Agile too.