diff --git a/packages/core/src/metadata/do_boostrap.ts b/packages/core/src/metadata/do_boostrap.ts
index 17190fceb2..09c1614afb 100644
--- a/packages/core/src/metadata/do_boostrap.ts
+++ b/packages/core/src/metadata/do_boostrap.ts
@@ -11,8 +11,8 @@ import {ApplicationRef} from '../application_ref';
 
 /**
  * @description
- * Hook for manual bootstrapping of the application instead of using bootstrap array in @NgModule
- * annotation.
+ * Hook for manual bootstrapping of the application instead of using `bootstrap` array in @NgModule
+ * annotation. This hook is invoked only when the `bootstrap` array is empty or not provided.
  *
  * Reference to the current application is provided as a parameter.
  *