diff --git a/Makefile b/Makefile
index df55045..45830f2 100644
--- a/Makefile
+++ b/Makefile
@@ -253,5 +253,6 @@ docs-serve:  ## Serve the documentation site locally with live reload
 
 clean:  ## Remove build artifacts and caches
 	rm -rf frontend/dist frontend/blob-report frontend/test-results
-	rm -rf backend/.pytest_cache backend/htmlcov site
+	rm -rf backend/.pytest_cache backend/htmlcov site \
+	  || echo "  ! not all removed (htmlcov/ root-owned? sudo rm -rf backend/htmlcov)" >&2
 	find backend -type d -name __pycache__ -exec rm -rf {} + 2>/dev/null || true