Shenzhen

In this context, "Bit by Bit" suggests a gradual or iterative approach to development or manufacturing, possibly implying a step-by-step process where components or features are added incrementally. "Cycle engaged" could refer to a continuous or repetitive process.
Outsourcing PCBA assembly to China is common due to the country's well-developed manufacturing infrastructure, cost-effectiveness, and expertise in electronics manufacturing. This approach allows companies to leverage China's resources and capabilities for efficient and high-quality production.