The fix may only take a day or two but what about the processes and transactions that should have been running in that timeframe?

What about all the people who now need to be put onto later flights, warehouses and factories that now need to catch up after being at a standstill for hours, transport being delayed due to paperwork not being able to be sent. And so on.

Those all need to be fixed up before everything is back to running as normal (until the next big screw-up).