diff --git a/JavaScript/4-bad.js b/JavaScript/4-bad.js
index a706074..a51dcb1 100644
--- a/JavaScript/4-bad.js
+++ b/JavaScript/4-bad.js
@@ -6,6 +6,9 @@
 const poolify = (factory, options, size, max) => {
   const instances = []; // Preallocate array
   for (let i = 0; i < size; i++) { // Use Array methods instead of loop
+    // In this case destructuring will be optimized by V8
+    // https://github.com/v8/v8/blob/074bb97050edcb45ca33b250ebcb865279e61dd4/src/compiler/js-call-reducer.cc#L4542
+    // It will change function to direct ::Call() that is C++ function instead of creation of iterator
     const instance = factory(...options); // Avoid array destructuring
     instances.push(instance);
   }