Afraid to overtighten the cleat bolts, I tightened them as I thought appropriate and went for a ride.
I encountered a stop sign at the top of short steep hill, and tried to clip out. Not a chance. The cleat swiveled on the shoe and there was no way to get my foot out.
I began to roll backwards.
I ski, and instinctively tried to put myself perpendicular to the slope so I would stop. That was my second mistake. I swung around and got slammed to the asphalt all the harder than I would have otherwise.
The only way out was to take my shoes off and leave them in the pedals while I walked back home.
I have other tales of incompetence ... let me think ...