Probably it was flagged by mistake. I did that once on a popular KOM route, where someone had posted a 55mph+ time. Someone left their garmin on driving home or something and I was trying to flag a "ride" for that, but it wound up a "hazardous route" flag and there was no way for me to undo it. I e-mailed in and they fixed it the next day; the route and all the previous times were back up.