Thank you so much for the detailed explanation, Kevin! I really appreciate you taking the time to explain how this works internally. Just to give you some context, I'm an iOS engineer, so my iPhone is almost always connected to my MacBook for development and debugging. I've always found the constant charging a little bothersome, which got me thinking about whether I could control it without physically unplugging the device. That led me to the idea of a simple macOS menu-bar utility that could toggle USB power on and off. I can also see broader applications, like scheduling when specific ports should supply power or automatically cutting power after a certain period. I'm aware that modern devices use USB Power Delivery (USB-PD) for power negotiation and have sophisticated battery management systems that regulate charging current, voltage, and temperature. Features like Optimized Battery Charging also help reduce battery wear. However, these mechanisms don't entirely eliminate lithium-ion battery degradation, particularly when a battery spends prolonged periods at a high state of charge or experiences elevated temperatures. I figured having some additional control over power delivery could be useful, especially for devices that remain connected for extended periods. Given the limitations you've explained, I'm now exploring a hardware-based workaround: a tiny USB-C male-to-female adapter with an Arduino-compatible microcontroller that could be configured and controlled directly from macOS. I'm still figuring out how feasible that would be, but it's been a genuinely interesting problem to explore. Thanks again for the insight!