Well yes, but one doesn't necessarily expect the same individual to stay on the bottom. Reason dictates that an analyst would either improve or exit the pool instead of continually failing (why would a firm hire a persistently wrong analyst?) So someone has to be at the bottom, true, but I think it's odd for someone to stay at the bottom.
That someone doesn't have to be at GS though.
How does the pidgeonhole principle apply to rankings?