In Forza 3, there's an icon I colloquially call the "slop" icon. It looks something like this:
I've figured out a few of the conditions for it, but a few more elude me. This definitely seems to happen whenever you collide with any other car, the walls, an obstacle, etc. (Including just a quick rub.)
But other times ... I swear I've seen it come up when I've had no contact with anything and have stayed on the track. I've seen laps start with it when the previous lap had it.
What are the conditions for this notification? It's not really detailed in the manual.