As soon as your feet get a little in front of your hips the “backseat” pattern can develop.
This often happens if you’re a little on the defense or if you are coming from a slower to a faster surface. In order to remain balanced you can do two things: 1) You can bend your upper body forward to compensate for the weight of your hips behind your feet. This will create a forward rotating torque, compensating for the torque from the hip weight rotating you farther backwards.
2) You can use your thigh and hip muscles to resist gravity and pull yourself back up from this position, into a good strong ski position with your hips over your feet again.
Option number 1 is not so good because:
a/ you lose vision ahead and thus your ability to anticipate
b/ you reduce your ability to absorb the shocks from uneven terrain
c/ it puts a lot of stress on your lower back
d/ style-wise it doesn’t look so great!
Option number 2 is by far the better solution, but it takes good strength and good knee stabilization. If you condition the muscles around the knees and hips correctly, assimilating the movements of skiing, you will get this strength and stability and reduce your risk of injury.