Consider a self-aware computer, somewhere in the space of minds. It’s smart enough to think about itself. But it can’t have perfect self-knowledge, due to Godelian infinite recursion issues. Hence, some of its parts must remain mysterious upon self-reflection.
The computer, realizing this, needs a label to describe the parts whose behavior can be observed, but whose detailed workings are (to it) inherently mysterious. In humans, this label seems to be “consciousness”.