Focus on Products Principle
This principle is a little problematic for Agile environments, because the product is not clear and we usually focus on the outcomes and values instead.
The main concern in the original PRINCE2 principle is to avoid focusing on "work", which is a very common problem.
Any project is done for its benefits and the business value it creates. These can be translated into the outcome (expected results). In predictive environments, it's also possible to translate the outcomes into the product, and that's why focusing on the product is a good advice. However, this translation is not possible or effective in Agile.
- Focus on Products principle at PRINCE2 wiki