Ever had good intentions go wrong?

[Resurrection]

I remember an incident from a number of years ago. Was walking through a car park when I noticed a car backing out of a parking spot with another car parked directly opposite. The person was having difficulty judging how much distance was behind their car and was inching back extremely slowly. So I thought I'd do the right thing as I was behind them and signal how much room they had. My intention was to wave them back until they were close enough and stop them once they go close to the other car. But so soon as I started waving my hand, the driver thought I was telling her she was clear and gave it a good dose of right foot. CRUNCH. The elderly couple got out of the car sand started abusing me. I stood there dumbfounded for a minute or so then walked away.