"What if?" is the key phrase here. Rescue work can be a very dynamic activity. That stable pinned boater may become unstable in a few minutes when they panic trying to escape their boat. They may have injuries that are not apparent from shore. Someone may slip on a rock and end up swimming. We set safety to protect ourselves from the unexpected. We also warn other boaters via our whistles to prevent them from hindering the rescue effort and making the rescue more difficult. If someone asks you to help and you don't feel you are up to the task, clearly communicate that to them. Don't give the old college try and end up needing a rescue. If you need professional help to treat a badly injured person, by all means send a runner for help. Moving a person with a neck injury is very challenging, especially without a decent back board in the woods without decent trails. Why risk permanent paralysis.