Re: The maths don't add up...
If the power goes off midway, restarting all the kit and removing all the half-done stuff, etc. is no easy task.
You're just assuming you switch it back on and everything comes back online, gets back to temperature and just carries on mid-process... hell, just a cheap PCB could be ruined if it's stopped mid-way through the process of creation (still soaking the copper off, in the middle of soldering, solidified residue from sitting around from 30 minutes, etc.)... now imagine nano-scale processes on a constantly-moving plant.
More importantly, if a brief blip COULD have cost you 10% of the month's supply, why do you not have generators to stop that happening?
But the answer to that is simple... if you're the only person making it, sure, you're delivery deadlines are hit. But you can still charge more because there's a dearth of your product worldwide. Same way that memory prices are generally volatile - supply and demand. Nobody's going to have spare capacity in a similar plant at a rival to "ramp up" and steal that 10% of revenue before you're back up and running, so you can get away with it.