Why did Martin Buber believe I-Thou relationships were uncommon between people?

Martin Buber believed that I-Thou relationships—characterized by a mutual, direct encounter between beings in the fullness of their existence—are rare because humans typically engage with the world through I-It relationships.12

In an I-It relationship, individuals do not interact with the "fullness of their being" but rather with only a fraction of it. Buber argued that this mode is common because it serves practical and functional purposes:2
* Objectification: We often reduce others to objects of thought, study, or action, such as in scholarly pursuits or social roles (e.g., boss and worker), where people are treated as tools or conveniences.12
* Survival and Science: The I-It stance is necessary for the creation of science and the management of daily life, including the manipulation of the environment and other people for survival.2

While Buber maintained that an I-Thou relation should be pursued whenever possible, he acknowledged that we must often settle for an I-It relation when necessary to navigate the demands of existence.2