The following configuration declares two services, each of which has the container_name specified.
But those container names are the same.

version: '3.4'
services:
  webservice1:
    container_name: foo
    image: nginx
  webservice2:
    container_name: foo
    image: nginx

I can run docker compose up with the above configuration.
But there will be an error at runtime from Docker,
so one of the two containers will not start.

Why doesn't compose validate this and issue an error before running any containers?