In our car, there's three levels of lane assist.

1. Hey, try to stay in the lines. If you start to veer, the steering wheel will do the smallest corrections and vibrate a lot.
2. The car will actively help keep you in the middle of the lane. (I mostly turn this on if I'm swapping my prescription glasses for sunglasses, then it goes right off again).
3. Same as #2, but if you put on a turn signal to change lanes the car auto changes when it's clear. (If you put your signal on with all this off and a car is in your blind spot it freaks out with beeps and vibrations).

I fucking hate #3. The only good part is it forces you to turn on the turn indicator. It both wants your hands on the wheel for the maneuver, but also will cancel the change if it feels any "driver correction".