diff --git a/scripts/build-all-in-one-image.sh b/scripts/build-all-in-one-image.sh
index a1437161e77..6ed9a5130f4 100755
--- a/scripts/build-all-in-one-image.sh
+++ b/scripts/build-all-in-one-image.sh
@@ -2,7 +2,8 @@
 
 set -exu
 
-if [[ "$1" == "pr-only" ]]; then
+arg1=${1:-'not-pr'}
+if [[ "$arg1" == "pr-only" ]]; then
   is_pull_request=true
 else
   is_pull_request=false