Nora, for these first ten months, you have always been sort of lazy, choosing the path that involves the least amount of work. When it was time for you to breast feed, you opted to have the milk extracted for you and, first syringed drop by drop into your mouth, and eventually placed in a bottle. At the moment you're at least a month behind your contemporaries (our friends' early 2009 babies) in the area of locomotion. It probably hasn't helped your progress that you have never liked being on your stomach. Especially ever since you learned to roll over, we barely even have time to snap back-fastening your pajamas closed sometimes.
In my search to rationalize your shortcomings, I've come up with a theory:
Babies raised in an environment with pets learn to crawl sooner.
It seems to me that if we had a dog or cat, we'd put you on the floor more with it, and it would also provide a target for you to strive to touch. Only recently have I been spending time on the floor with you holding books and toys just out of your reach in attempts to motivate you to actually do something. The minute I stand up from the floor your entertainment level passes below your annoyance of being face down threshold and you flip over onto your back.
So far your training is going well. Once you actually got your rear end into the sky and up on both knees, but there was no way you could get your face off the ground then. And you're pretty good at pushing your chest off the floor, but then the legs are immobilized. The phrase "Baby steps...baby steps..." is ironically appropriate here.
In this video, amidst the general whining and complaining, you learn an invaluable lesson: Don't lick the floor!
Oh, and watching this video makes you cry. I think you feel sympathy for the poor face down baby in the video.