It's a bad analogy. Autopilot just maintains the aircraft in some state, then there's the flight director which maintains the flight path, and you can connect or disconnect the two at will. When connected the director can change the autopilot state.
To use the flight director you must fully specify your flight. The weight, the fuel, the weather, expected winds, takeoff and landing runway length, runway conditions, expected brake demand, as well as every single waypoint you're going to cross and the expected state at that crossing.
> what the human metaphor means
We learned after high levels of cockpit automation that maintaining situational awareness was still required. Pilots are freed of some stress during high workload portions of the flight, provided they planned correctly in advance, and that zero changes to their flight plan (not likely) occur.
As a result pilots are mostly told and trained to hand fly the plane during take offs and landings if the weather allows for it. You should only use high levels of automation if the situation demands it.