As mentioned before most people drive in a way (besides distracted and incompetent) that avoids quick movements and sort of "drifts" around from lane to lane. Slow lazy lane changes that scoop wide to the opposite side before slowly finding enter of lane. Lots of overcompensating for perceived movements etc. When a driver typically starts to "feel" the weight transfer in their vehicle they seem to get that 'oh crud' feeling and try to avoid it.
For instance, most cars can quickly stop in a decent distance but often people don't stop quick enough because everything in the car will shift and fly forward. Instead of really firm steady full pressure they brake at 3/4 pressure and do a big right or left turn off onto a shoulder, potentially causing more problems.
What's even scarier is the many many times I see distracted people drifting into the bike lanes or shoulders when I'm in a car behind them. I always imagine that's where I could have been.