If it's just a touchscreen or hardware buttons, you may need a key to open a panel where the keyboard/mouse are, or to bring your own keyboard/mouse, in order to navigate the Windows part of the interface to fix the problem.
Obviously if it's intended to be networked to existing desktops for control over a LAN, the client software will be Windows, but even then you hope the server isn't.
Outside our tech bubble working on Unix is still perceived as hollywood-style hacking of the bank and folks really have no clue, unless its done in GUI just like... you guessed it, Windows. Folks wouldn't even touch it.
Windows is an awful choice for any system that must be reliable. I know, because the industrial control system at my workplace used to be windows, and cost us mega bucks every year in down time. Now it's Linux, and we haven't had ANY downtime in over two years.