Different steels have different edge holding capabilities. Chrome is a very hard metal, and adds hardness to steel. Vanadium is a brittle metal, adding toughness. Adding chrome and vanadium to steel in the right amounts gives steel hardness as well as strength. The end result is a steel that holds an edge but doesn't go dull after repeated use. If you have a knife that dulls quickly, it's not CV steel.
CV steel is very flexible. The University of Toledo states CV is used for automobile springs and connecting rods where a durable steel that is not brittle is required. A CV knife's advantage is that it's almost like a spring, easily bendable without breaking. For example; a fillet knife must follow a bone closely, so it must bend without breaking. A CV filet knife does this. If a knife is not made out of CV, it breaks easily when bent because its too brittle.
Both chrome and vanadium are non-rusting metals. A knife blade made out of CV does not rust as easily as knives made with other steel alloys. Rust resistant, however, does not mean rust-free. The knife must still be dried and lightly oiled to prevent rust formation. However; it can air dry, as opposed to hand-drying after washing.
CV is stronger than many other steels, such as a plain carbon steel. For example; meat cleavers have to be strong, and able to split through bone like a hatchet. If the same force is applied to a "cheap" cleaver as a CV cleaver, the cheap steel cleaver will break. Also, if a serrated knife has to cut through bone, a CV steel knife will not break or chip teeth.