diff --git a/hack/tf-fmt.sh b/hack/tf-fmt.sh
index b863171a803..e36822a1653 100755
--- a/hack/tf-fmt.sh
+++ b/hack/tf-fmt.sh
@@ -2,7 +2,7 @@
 
 # in prow, already in container, so no 'podman run'
 if [ "$IS_CONTAINER" != "" ]; then
-  if [ "${#N}" -gt 1 ]; then
+  if [ "${#N}" -eq 0 ]; then
     set -- -list -check -write=false
   fi
   set -x