Why in the world would a motorist need to know that there is a damaged guardrail ahead? Would this cause someone to alter their driving to ensure that they pick another suitable location to careen into a perfectly suitable guardrail?
If anyone knows the justification for such a sign, please let me know. I feel that litigation or the fear of litigation is a likely explanation for the sign but I am holding out hope that there is another explanation totally unrelated to the legal system.