This seems somewhat "harsh", why does the system work like that? I got a Hyundai and it has a lane assistant which keeps you in your lane, but it doesn't freak

This seems somewhat "harsh", why does the system work like that? I got a Hyundai and it has a lane assistant which keeps you in your lane, but it doesn't freak out when somebody passes you. Braking, when you run up to a slower vehicle in front of you, is sometimes a bit stronger (depending on the speed difference), but it's not alarming either. I know of dead spot assistants which light up in your mirrors if you have a car in the dead spot, but those don't beep either. What kind of assistance system does your wife's car have? Just to avoid that... :-D