From reading here, it seems that falling down is not a unique occurrence to just me. I haven't fallen since I was a tween (but did fall about a week ago), so it was strange for me to read other adults falling down.
What are the reasons you have fallen down? Was it b/c of klutziness in general, tire failing to grip due to lost traction on water or sand, etc?
Myself, it was b/c I came off a smooth curve (not at an angle) parallel to water rolling down the gutter. My 700x32 tire lost grip and I fell.