The Fade Finish
The body is in a unique position during the fade finish. The right shoulder is much lower than in the draw finish and hasn't traveled around toward the target. The left elbow is higher than the clubhead, and the torso remains very tilted to the right. This finish encourages the club to swing more to the left after impact, restricting the full release of the club.
To produce a predictable, left-to-right ballflight, the club must move to the left immediately after impact.
The Draw Finish
When you're after a subtle right-to-left ballflight and want to swing more naturally, focusing on your finish can be a great trick. The draw finish should have the right shoulder higher and more around toward the target with very little bend remaining in the torso. Focusing solely on the finish should allow you to produce a subtle draw with ease.
The finish for a right-to-left shot (draw) should feature the club coming up through the left shoulder.