I suspect this is a very stupid question so my apologies if this proves to be the case.
Throughout a standard Quali session, the track will be fastest for the last car to cross the start/finish lap (excluding weather variations) due to rubber being laid down constantly. Therefore, crossing the line last is relatively valuable. Why isn't there a constant battle, particularly in Q3, to be the last one over the line? We've seen it occasionally over the years but it seems to be quite rare. I've long suspected that the teams come to a decision between themselves about the order in which drivers will cross that line specifically to avoid multiple drivers having their laps compromised due to jockeying for position. This would go out of the window under changeable conditions and, perhaps not coincidentally, it's on these sorts of occasions that we see driving messing about with each other. Basically I was wandering how true that might be and, if it's not true, what the real situation is?