Another analogy is that you have a bakery that produces soufflés on an industrial scale.
These soufflés take two months to bake. The baking has to be done in such a precise fashion that even fractions of a degree in variance results in the entire batch being ruined.
Worse still, it takes a long time to bring the oven up to temperature and stabilise it on the precise temperature. You can't just scrap the batch that's ruined and start production again.
These soufflés take two months to bake but you need soufflés every day for sales. What does this mean?
You always have 2 months of soufflés in various states of production at all times.
Now you lose power and all these as very fragile soufflés in production are lost because of the power failure. Furthermore, it will take you two months to get the first soufflés off the restarted production line.
These soufflés take two months to bake. The baking has to be done in such a precise fashion that even fractions of a degree in variance results in the entire batch being ruined.
Worse still, it takes a long time to bring the oven up to temperature and stabilise it on the precise temperature. You can't just scrap the batch that's ruined and start production again.