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For example, if you're at your BIOS screen or a DOS environment, when you plug in a new USB keyboard, it appears to be usable almost instantly. But, if you are in Windows and plug in a new keyboard, it has to install drivers or updates, making it unusable for the duration. I realize that you don't get full features of certain keyboards in DOS, so Windows has to install drivers for added functionality. But why doesn't the keyboard start working with basic functionality instantly and continue to install the rest of the drivers if needed, obviously the technology is there to make this happen.
This is more for curiosity than to solve a problem, but any insight is appreciated!