There are some similarities with hardware hack reform that involve tearing down a wall: unless someone actually starts and unlocks things, can’t wait to tell you what kind of complexity might be hidden. [voussoir] There’s a project that shows this nicely: There have been a number of minor issues with the process of replacing a rechargeable mouse with a USB-C instead of a micro-B. In fact, changing the original reservoir was the easiest part!
On the one hand, the mouse in question seems to be a perfect candidate for easy change. The enclosure is not very difficult to open, there is enough space inside and USB is only used to recharge the battery. So what was the problem? The problem is known to anyone who has worked to replace an existing piece of hardware: existing parts are the boundaries of hacking work, and some are less easily changed than others.
Inside [voussoir]In this case, the first minor problem was that the small PCB hosted the original Mini-B receptacle had a screw hole in it, which was used to secure it during repeated plugging and unplugging. Confirming the new USB-C receptacle using the same screw was a bit of a hassle, but there was another problem after tackling it: [voussoir] The mouse mounted the new USB-C receptacle flash with plastic, but it didn’t let a wire sit perfectly. The reservoir needed to expand a bit, or the charging cable could not plug in enough. Go back to the workbench, and so it went for a few more repetitions.
The change was successful in the end, but the fire test shows how working around the limitations of the physical design can lead to unexpected problems. This is bad enough when someone changes a small piece of hardware with an existing mouse, let alone completely redesign the old Apple rat design for modern computers.