1, its own characteristics, in addition to its accurate tangent, small incision, one of the larger features is its wear resistance, even the same blade made of material has wear resistance.
2, like this circular design, when it works, not all the knife work, but by rotation, only a third or a quarter of the area of contact with the cutting object, and contact surface has a very good flow.
3. In the case of wear, it is also increasingly caused by heat and wear. Some heat will be generated during the friction between the cutting blade and the cutting object. Avoid use, but this round blade dissipates heat very well. Other blades do not have this advantage, so wear will increase.