What Exactly Does Biden Mean by ‘Finish the Job’?

Decades ago, I wrote and produced a (not particularly good) documentary called Gargoyles: Guardians of the Gate. My figurative fecal-gifting colleagues always liked to ask me, “What gate?”
I’d often reply, “Exactly.” Other replies might have included, “I dunno,” “shut up,” “work with me, man,” and “buy it and find out.” The truth is they’d ask me a lot, and since the nature of this gate was somewhat ephemeral and mysterious, conjured as much for reasons of alliteration as historical literacy, I could never give a dispositive answer.
All this came to mind when I watched Joe Biden’s reelection announcement video.
Biden’s 2024 slogan is “Finish the job.”