Because it bent and had a perfect centered flex point.
Explanation: Greg has posted a very good description of skiing steeps and high angle carving. He hits some great points. Just like you can't go 26 mph uphill with a steel bike frame unless you are doping, you can't get high angles on some skis, even some carving skis. Like Greg says, 13-meter skis (with a 65mm waist) don't give you enough platform on soft snow.
They do on hard snow or ice however, the risk factor goes way up. By risk I mean you have to have super sharp edges on your skis and you have to get the tip pressured to start the carve. This requires at least racing background maybe even FIS levels. If you screw up; get jetted, the consequences are not funny.
The easiest and safest way to learn is to have perfectly groomed corduroy that has a slight give. A ski of about 72cm to 76cm is ideal. The ski should be soft enough to bend from the middle and the tip should be wide enough to pull you through the arc. My runs on Dreamcatcher are on TT80 Head skis that were 67cm underfoot. I have a pair of Euro version Myia's that have the same sidecut now. Not the best set up for tight high carving, but they ski very well.
A center flex point means when you are at the apex and fully committed the ski will continue bending at the same rate. Tightening the radius at this point is crucial. I do it by flexing slightly and then increasing the tipping and CB.
If the tail of the ski is too stiff it isn't a center flexing ski. A stiff tail will jet you out or accelerate you too early. This means your feet won't stay under your hips which means big speed and a less than a finished arc.