Why does a horse breeder practices eugenics with two winning horses?

Horse breeding, like many forms of selective breeding, does not involve eugenics. Eugenics specifically refers to the selective breeding of humans based on certain genetic or phenotypic traits, with the goal of improving the human population. However, when it comes to horse breeding, the goal is to enhance desirable traits specific to horses for various purposes such as racing, sports, or physical attributes. This practice aligns with selective breeding for desired characteristics rather than eugenics.