"Happens to the best of us" is a saying I use often. As you saw all it takes is one moment of inattention or distraction sometimes. I was riding my motorcycle one day and was doing a little math in my head and almost crashed/missed a turn. This after 50,000 miles of riding a motorcycle in four years. Have over 100,000 miles on the bicycle and the other day simply flopped off the front while trying to mount it. Fell on my back in front of my office in front of co-workers - and one that just said "be careful!"