Maybe you are making dinner or washing dishes in another room. And thus you end up missing some key moments such that when the show ends, you are not quite certain exactly what happened.

I just finished a book where that essentially occurred. Reading late at night while I was starting to doze off, I think I either missed some key moments or did not fully grasp their import. And then when things "wrapped" up at the the end, I was left wondering what the hell had just happened.