I notice that Windows 10 seems to spend a lot of time "preparing to install updates" before it actually gets on with it. I also note that for most of that time, the progress bar doesn't advance at all. Like how it just now stayed at 10% for a long time (I didn't clock it, but I don't think I'm exaggerating if I put it at a few minutes), then jumped to 68%, relating to a single update.
Because the text alone is apparently not clear enough, here is a screenshot of the specific Windows Update step that I am asking about (follow the link to see the full screenshot from which the below has been cropped). Note that the screenshot was taken during a different update session than the one I am talking about in the first paragraph, hence the percentage complete is different.
What does Windows actually do with all this time? What "preparations" are taking it such extreme amounts of time?
Note that I am not asking about the actual installation of the update.
While the particular time that prompted me to ask this question was in a VM, I'm seeing similar behavior with Windows 10 running on actual hardware, so I don't think it's related only to the fact that it's running in a VM (even though that could perhaps be a factor).