That ' s not true . A concrete wall is pretty much guaranteed to bounce you back due to conservation of momentum . That ' s why metal guard rails are designed to fail . The post gives out and the metal band catches the car in place . Also important to remember that a guard rail has to work for everything from a little coupe to a double trailer truck <| sep |> People were asking the same question last year when Luck got hurt . people are stupid sometimes . <| sep |> I don ' t get it . By the time I was 21 I had the mature , sensible attitude to drinking my parents had at home , loudly screaming obscenities into the bin between bouts of vomiting , because I had mistaken it for my ex . <| sep |> Possibly an attempt at humour , which fell fairly flat .