I had no say in when or how Windows would update.
This was something that made me go absolutely ballistic with my work laptop running Windows 7. The factory-default setting is to install any and all updates whenever they are available. After wrestling with this for a while, I realized that I could set it up to download and install updates whenever I manually ask it to check for updates.
But even then - how can a company like Microsoft, with VERY intelligent people, have such a completely, utterly, $^(%*&#(*%&(@%$ for brains procedure to install updates - ON A LAPTOP - when you shut down the system, when it says "DO NOT TURN OFF THE LAPTOP DURING THIS UPDATE". Can't they have a simple override button you click, and at least give you an estimated duration for the update to be installed? The worthless "X% complete" means nothing - I have seen that screen stay on the same percent after an hour (for a major update), and I have seen it flash through an entire update in just 20 seconds.
Don't they realize that when you are using a laptop, you may not always have the luxury of putting it in sleep mode or hibernation to avoid an update? Or that maybe you don't have access to an outlet to power your laptop for an update for 30 minutes? Or maybe a memory-intensive 3D modeling program crashes and you want to reboot to avoid further issues of losing your unsaved work (yet again), and you don't want to install your updates right then and there in the middle of the work day?
I have had several times where I am at a jobsite, or some other location where I had to reboot due to a program crash, or told it to shut down and didn't go through the steps at a snails crawl to check that there weren't any updates to install, and I had to sit and wait for many minutes for the computer to finish installing before it shut down and I could leave. Thank God I wasn't on an airplane! I don't think you could tell the flight attendants right before takeoff "Sorry, but my Windows laptop just started an update, and after 5 minutes of updating, it's only at 15%, and I have no clue how much longer this will take, so I can't just shut it off even though the FAA requires it".