Not much to say on this beyond what Kees said already: "When that log information is not treated appropriately and with due care, it is useless when it is really needed: in the middle of determining the impact of an incident, while containing and mitigating the effects of an incident, or as a post-mortem forensics analysis. Reliable log information is of crucial importance. Knowing the environment that generates the log information makes it even more useful."
But then again, we all said it a dozen or so hundreds of times :-) What makes them act? Of course, good ole FUD or chanting the C-word ... :-)