Consciousness isn't even constrained by the brute facts of existence. It sounds insubstantial. The idea makes us anxious and we worry that maybe we are really nothing after all. To avoid that dreadful possibility we try to become a nice solid thing like the objects around us. We try to objectify consciousness to escape the fluidity of experience.
Subjectivity tries to be an object instead of accepting the fact that it is a subject.
Or as Sartre liked to put it, being cannot exist within non-being. The principal motivation of transcendental subjectivity is thus doomed from the beginning, said Sartre. I can appreciate what Sartre was getting at by saying that transcendental subjectivity is motivated. And it does want to be unified with wholeness. It wants to make itself into a genuine self-containing unity of everything.