Couple of years ago we had a Windows 10 computer decide to update itself despite having been told to only do it on a schedule. It was the early days of W10 - I'm sure you remember the tales of people's laptops rebooting in the middle of presentations. This machine wan't even connected to the internet at the time, and hadn't been for several days, so it had downloaded an update but had saved it up, somehow. Anyway, it just went ahead and started the update process, except it stalled during the restart and we had to power cycle it and manually fix it. Took half an hour to get the update installed. Which doesn't sound too bad, until you realise that it was running the sound cues for a theatre performance and while it was sulking we were dead in the water. We had to abandon the performance and refund the audience. The Mac running Qlab arrived before the next show in the schedule. Shame, as the actual application it was running at the time (SCS) was quite a nice bit of software.