Tailscale improved its product by utilizing Apple's open source code, allowing for better performance and functionality. The company's use of open source code has sparked a discussion about the importance of transparency and open source software. Tailscale's decision to keep some of its code proprietary has been met with criticism from some users. The company has explained its reasoning for keeping certain parts of its code closed source, citing the complexity of its control server and the need to focus on supporting its own infrastructure.