To understand the separation between the circles you have to be aware of my definitions of the terms. In my teaching, carving and steering do not overlap, they cannot coexist. Carving is a ski tail following the ski tip in the same track, leaving a single line in the snow. Steering is introducing any degree of skid angle. As soon as a skid angle is introduced, carving ceases to exist and steering is born. There's no shared space with those guys, no overlap.
Pivoting too is a separate turning tool too, which is done independent of carving or steering. It's manually redirecting the skis while they are disengaged from the snow. While it's being done it does nothing to change the direction of travel of the skier, but once the skier reconnects with the snow and engages the edges the effect of the pivot is to sharpen the turn shape beyond what could have been done through carving or steering alone. So it's a skill that has a major influence on turn shape, and thus deserves its own circle in this drawing.
Obviously,for those who harbor different definitions of these 3 terms, this drawing my need to be altered. Or you can just trash can it totally.
You may notice that I have different sizes for the carve/steer/pivot circles. It's not cast in stone, and can change from run to run. Just my general feeling on the prevalence of usage of these turning techniques across the spectrum of good skiing as performed by good skiers. The areas of the carving/steering/pivoting circles outside of the good skiing circle? Poorly executed versions of those skills. And the blank spots within the good skiing circle? Use your imagination.