diff --git a/modules/performance/php-optimizer.sh b/modules/performance/php-optimizer.sh
index 0b99741..857ee4c 100755
--- a/modules/performance/php-optimizer.sh
+++ b/modules/performance/php-optimizer.sh
@@ -991,7 +991,7 @@ optimize_multiple_domains_wrapper() {
         optimize_domain_direct "$domain" "$username"
         local result=$?
 
-        if [ $result -eq 0 ]; then
+        if [ "$result" -eq 0 ]; then
             optimized=$((optimized + 1))
         else
             failed=$((failed + 1))