Status code ranges are less about fault than they are about determining whether the client can retry the request without changing it.<p>5xx means that the client can, because there&#x27;s a chance repeating the request will succeed. 4xx means the client shouldn&#x27;t, because it needs to change in some fashion before it will work.<p>This is so that clients that don&#x27;t understand a specific status code can fall back to the more generic x00 code and still behave sensibly.