diff --git a/packages/grpc-js-xds/scripts/xds_k8s_lb.sh b/packages/grpc-js-xds/scripts/xds_k8s_lb.sh
index ca747f7ea..b87e3306c 100755
--- a/packages/grpc-js-xds/scripts/xds_k8s_lb.sh
+++ b/packages/grpc-js-xds/scripts/xds_k8s_lb.sh
@@ -167,7 +167,7 @@ main() {
   local failed_tests=0
   test_suites=("baseline_test" "api_listener_test" "change_backend_service_test" "failover_test" "remove_neg_test" "round_robin_test" "outlier_detection_test")
   for test in "${test_suites[@]}"; do
-    run_test $test || (( failed_tests++ ))
+    run_test $test || (( ++failed_tests ))
   done
   echo "Failed test suites: ${failed_tests}"
   if (( failed_tests > 0 )); then