I wake up and head to the bathroom. Out the window, I notice that the sun is rising through the haze so that it is a red and comfortable to look at. "I wonder if there's enough light to take a decent picture," I say to myself. So I grab the camera, put the batteries in (I've started taking the batteries out when I'm not using the camera, in order to lengthen their life), come upstairs, take a reading (good), grab film, insert film in camera, shoot half a roll. I'm satisfied that at least a couple of the pictures will turn out well.
I head back downstairs to take the batteries out and put the camera away. I sit down, put the camera in my lap, and open up the back.
Lesson learned, I guess. Like that time I thought I had the film loaded properly, shot a whole roll, and then found out that I did not in fact have the film loaded properly so that none of the pictures actually got put onto the film.