We trust some people over others because we have no choice but to trust them.
Take babies for instance. Babies trust no one. Babies do not want to know anyone besides their mothers, and to cleave to their mothers. To the extent in which the babies grow up and get to know their environment, from their crib to their room, to their entire home, and perhaps their backyard, then these babies somewhat develop trust toward people in these familiar surroundings to the extent of their familiarity with them. Babies then approach those who are closer and more familiar, and stay away from others who are unfamiliar. In other words, trust is a trait that we need to acquire.
Then, to the extent in which we gain familiarity with our environment, our society, the surrounding world—determining who is closer and further away from us—we accordingly develop trust in certain people.
We can also see such examples in animals. There are animals that we have domesticated over the course of history, such as cats and dogs, which we have established a certain amount of trust with. We know that we likely cannot raise a lion at home, but we have developed a level of trust in some animals over time—where the animals trust us to a certain extent, and we trust them—and then we can take their offspring and begin to develop a kind of relationship according to the degree of trust that we have established.
𝘉𝘢𝘴𝘦𝘥 𝘰𝘯 𝘵𝘩𝘦 𝘷𝘪𝘥𝘦𝘰 “𝘞𝘩𝘺 𝘋𝘰 𝘞𝘦 𝘛𝘦𝘯𝘥 𝘵𝘰 𝘛𝘳𝘶𝘴𝘵 𝘚𝘰𝘮𝘦 𝘗𝘦𝘰𝘱𝘭𝘦 𝘖𝘷𝘦𝘳 𝘖𝘵𝘩𝘦𝘳𝘴?” 𝘸𝘪𝘵𝘩 𝘒𝘢𝘣𝘣𝘢𝘭𝘪𝘴𝘵 𝘋𝘳. 𝘔𝘪𝘤𝘩𝘢𝘦𝘭 𝘓𝘢𝘪𝘵𝘮𝘢𝘯. 𝘞𝘳𝘪𝘵𝘵𝘦𝘯/𝘦𝘥𝘪𝘵𝘦𝘥 𝘣𝘺 𝘴𝘵𝘶𝘥𝘦𝘯𝘵𝘴 𝘰𝘧 𝘒𝘢𝘣𝘣𝘢𝘭𝘪𝘴𝘵 𝘋𝘳. 𝘔𝘪𝘤𝘩𝘢𝘦𝘭 𝘓𝘢𝘪𝘵𝘮𝘢𝘯.