I was recently at a burial in our local cemetery and there was an open grave behind the one which I was attending, with a piece of warped plywood, half covering it. The cemetery crew had opened it up for a committal service, and then there was bad weather, so the service was postponed, and had not yet been rescheduled and the person I was talking to from the vault company said it has been like that for a couple months. Things do happen, unfortunately, that can cause injury or harm, not intended either due to staff shortages, general failure to inspect, or vandalism. You always have to be aware of your surroundings.