Earlier quoted context omitted.
I'm terrified. I saw John Deere code, and its tortuous. Nobody should try to fool with it without serious study.
This is also true of elevators. The vendors intentionally write awful code so that only they can fix it.
The lifts had no buttons inside the car, your security tag would program in the floor, so you had to get in the right one otherwise you’d be stuffed.
There was a restaurant open to the public at the top, so in the evening the lifts would be full of forlorn diners trying to find their way out.
The computer would often crash and reboot mid journey - the lift would stop, the lights would go out and the screen would run through a boot sequence, before starting up again.
I once saw a technician tinker the system and he genuinely had a bunch of five inch floppy disks.