Now that's a true statement that happened to me. Back in the day when I first started racing motorcycles I bought a '69 Ford Econoline van with a 3-speed manual on the column trans and a 300 inline six. I parked it in a friend's very steep Pittsburgh area driveway and was in the garage, door closed, with friends working on rating fork springs when we hear four or five cars honking their horns and they were not stopping. Opened the garge door and my van, that I had left in reverse, without the parking brake on, was now down the steep driveway blocking both lanes of the two lane street and only a few feet from heading down what was basically a cliff to nowhere. Got lucky that one it didn't hit anyone or a passing car and two that it stopped before it went over the cliff to nowhere, It may have creeped down the driveway bleeding off compression and that might have saved the day. From that point on I used the PARKING brake and even with an automatic, well most of the time with an auto trans but for sure ALWAYS with a manual trans always crabbed or turned the wheels to the curb or where it might go if it takes on a mind of its own

Mike