It doesn't; it just needs to know it was called. You make your selection once it arrives.

Look up the early history of elevators and you'll see a progression from fully manual in-car up/down controls (often with a dedicated human operator); various semi-automatic systems with minor improvements like automatic leveling and door control; and then operatorless systems that started with nondirectional calls:

https://liftescalatorlibrary.org/paper_indexing/papers/00000...

On the ground/lowest floor, there's only one button as there's only one way to go.

It is reasonable if you either have low load say a residential building where lift is often idle. Or low number of floors where travel times in either case are short.

i just saw this for the first time today in Romania...