The dotted line is an average path. The good racer, in green, leaves a clean, thin track.The "bad" racer is shown by the thick black line; the uneven thickness indicating skidding.

It was amazing to see that at the same spot, point A, the green racer is already turning left while the black racer is still completing his right turn and scraping off speed by skidding at point B to get back into the course before the next gate.  This is called "being late" in your turns. The black racer waits until he is at the gate before he starts the next turn ("E"). Then there's not much time left to complete the turn before the next gate.

The green racer sets up for the turn early (at "C"), and starts a very gradual turn, arcing his way around in a fairly wide-radius turn. A wider radius means a straighter line.

Notice the green racer plans his turns so that by the time he/she reaches the gate, his/her skis are already pointed toward the next gate.  Meanwhile, the black racer's skis are still pointing to the outside of the course, and he has to try to whip them around quickly, making jerky zig-zag turns.