Marine deputies cannot back a boat trailer

I had a 14 ft runabout and the boat launch was a steep drop off. I backed it down perfect and unhooked it and away we go.
When we got back my wife decided to back the trailer into the water. She wasn't bad at it really.
The steep slope really messed her up and after several attempt I said "Put it in park."
This trailer wasn't real heavy but heavy enough. So I walked to the back and grabbed the back end and lifted it up and straightened it out.
One guy was watching and said "I've never seen it done that way before".