diff --git a/dbench b/dbench
index 32ab65b8..5dd85ce0 100644
--- a/dbench
+++ b/dbench
@@ -98,7 +98,7 @@ done
 set -- "${positional[@]}"
 
 site="$1"
-if ! $1; then
+if [ -z "$1" ]; then
  site="site1.local"
 fi