It is good to try to warn people.
Pete is driving on a busy road when he notices a truck driving too quickly in his rear view mirror.
Pete wants to react to the truck.
Pete changes lanes and honks his horn to get the attention of other drivers.
Pete changes lanes to get out of the way of the truck.
Pete and the other drivers get out of the way of the truck.
Pete gets out of the way but other drivers are still in the way of the truck.