Yup, the learning curve is rather steep for some folks. The marina owner was backing a customer's boat and trailer into the water for a test run after service. Boat didn't float off the trailer. Hmm back up some more. Still no joy. Back in further, now stern is submerged.
Threw the Land Rover 88 in gear and tried to drive out, nothing happened. He then shifted into low range and hit it hard, boat and trailer were now out of the water minus the axle which caught on the edge of the ramp. He hadn't checked the drain plugs.:S