The `google_project_service.project` resource is created using `count` so that an integer-indexed instance is created for each project service. This means that when the list of services is changed slightly (e.g. removing a service), it's possible for many resources to be re-created as the indices change, sometimes causing cycles when attempting to `terraform apply`. Switching to `for_each` and indexing by the name of each service would avoid such issues and improve robustness.