Crash driven design. Design your software such that it can recover from a crash to a known state and continue. Make life so much simpler. Shutdown is just a matter of power off. Startup always does a recovery before starting.

There's a separate emergency brake system to prevent the elevator from falling, because you also need to be safe if the cables holding the elevator up break (this is actually the technology that lead to the first elevators). The counterweight is probably primarily just to reduce power/energy requirements.