I guess you don't remember when it came out that a Windows 95/98/Me machine, running nothing at all, would crash spontaneously after, what? 39? days, when a time counter rolled over. No one had noticed, in years prior, because: No one had ever got one to run that long.

Boeing 787s need to be fully power-cycled every few months, for identically the same reason, although its time counter ticks less frequently. They would fall out of the sky, otherwise. It is just lucky somebody noticed before it happened, because there has otherwise been no need to reboot it.