Which principle applies directly in the context of Agile Release Trains?

The principle of continuous delivery of valuable software is fundamental to Agile Release Trains (ARTs) because ARTs are designed to provide a steady flow of value to customers through frequent and reliable releases. This aligns with the Agile philosophy that emphasizes delivering incremental improvements and features that enhance customer satisfaction and experience.

In the context of an ART, teams work collaboratively in a cadence to ensure that they are consistently delivering work incrementally, allowing for quicker feedback cycles and the ability to adapt to changing requirements or priorities. This principle encourages transparency, collaboration, and customer engagement, all of which are essential for successful Agile implementation.

The other options do not resonate with the core goals of Agile practices. For instance, focusing on individual performance is opposed to the collaborative nature of ARTs, where teamwork and collective ownership of outcomes are prioritized. Adherence to rigid planning contradicts the Agile principles that promote flexibility and adaptability. Extensive documentation is not emphasized in Agile methodologies, which prefer working software over comprehensive documentation. Thus, the emphasis on continuous delivery of valuable software is what makes it directly applicable within the ART context.