It's the default value for --incremental=.
f"--cache-only={main.cacheonly}",
*([f"--workspace-directory={os.fspath(p)}"] if (p := main.workspace_dir) else []),
*([f"--package-cache-directory={os.fspath(p)}"] if (p := main.package_cache_dir) else []),
- "--incremental=no",
*([f"--package={package}" for package in main.tools_tree_packages]),
*([f"--package-directory={os.fspath(directory)}" for directory in main.tools_tree_package_directories]), # noqa: E501
*([f"--build-sources={tree}" for tree in main.build_sources]),