One of the great ironies of "Crossing the Bar" is that the speaker's departure from the harbor—from life—isn't really a departure at all. In one way, the speaker seems to suggest that he is leaving a world in which he never really belonged and is finally returning home. The soul's true home is not the "bourne of Time and Place," but rather the open ocean, beyond the bar.
This poem shows us that death is a departure, sure, but it is also a homecoming for the soul.
If death is a homecoming, then life ("the bourne of time and place") turns out to be a place where a person doesn't really belong (at least not permanently).