Which statement is true about a Value Stream that successfully uses DevOps?

A Value Stream that successfully uses DevOps embodies a closed-loop process of learning, which is essential for continuous improvement and innovation. This characteristic allows teams to rapidly iterate on their products and services by drawing insights from real-time feedback and performance metrics. With a closed-loop feedback system, teams can identify areas for improvement, test hypotheses, and make data-driven decisions that expedite the delivery of high-quality software.

This culture of experimentation and learning fosters an environment where teams continuously optimize their processes, tools, and practices, which is a fundamental principle of DevOps. It enables organizations to adapt quickly to market changes, customer needs, and technological advancements, ultimately leading to more effective and efficient delivery of value.

Regarding the other options, while they may contain elements that could be beneficial in a DevOps context, they do not capture the overarching principle that a closed-loop learning process provides. A technology stack without legacy code is not realistic for most organizations as legacy systems often coexist with new developments. Objective measurements with automation are indeed important, but they don't alone ensure continuous learning or improvement without the feedback loop. Lastly, a lower threshold of defects approved to production focuses more on quality control rather than the broader perspective of a learning culture essential in successful DevOps implementations.