Why don't European warriors have a tradition of using knives?

Combat knives developed with the emergence of cavalry. Early infantry used a double-edged sword, which was sharp and could cut and stab, and the harm of stabbing was far more serious than chopping. After the cavalry appeared, knives, thick ridges and single blades were produced, which were not easy to break. And because of the speed of the horse, the knife has terrible lethality. In China, knives appeared in the early use of chariots, but after the chariots were eliminated, a large number of cavalry used knives as standard equipment. European cavalry appeared later and less, and the scale of the early war was small, so they were not used to knight array attack, so a large number of swords were equipped instead of knives. The appearance of knight plate armor made the role of knives smaller, so the cavalry used a lot of long weapons, heavy weapons and blunt weapons in the later period, that is to say, European knives were eliminated before they worked, so the tradition of European warriors was swords and blunt weapons.