1. Make uses mtime to determine whether inputs have changed. Bazel uses a hash of all inputs to the target (file contents + other inputs like environment variab

1. Make uses mtime to determine whether inputs have changed. Bazel uses a hash of all inputs to the target (file contents + other inputs like environment variables) 2. Make lets you define inputs and outputs, but doesn't enforce them. Bazel sandboxes build actions; if you try to import a dependency that you haven't listed as a direct or transitive dependency, the build will fail. This is leads to users never (or at least very rarely) having to run `bazel clean`.