diff --git a/src/Microsoft.AspNetCore.Mvc.ViewFeatures/Controller.cs b/src/Microsoft.AspNetCore.Mvc.ViewFeatures/Controller.cs
index a4ad48b4f6..5c680ffaaa 100644
--- a/src/Microsoft.AspNetCore.Mvc.ViewFeatures/Controller.cs
+++ b/src/Microsoft.AspNetCore.Mvc.ViewFeatures/Controller.cs
@@ -25,9 +25,16 @@ namespace Microsoft.AspNetCore.Mvc
         /// Gets or sets <see cref="ViewDataDictionary"/> used by <see cref="ViewResult"/> and <see cref="ViewBag"/>.
         /// </summary>
         /// <remarks>
-        /// By default, this property is activated when <see cref="Controllers.IControllerActivator"/> activates
-        ///  controllers. However, when controllers are directly instantiated in user code, this property is
-        /// initialized with <see cref="EmptyModelMetadataProvider"/>.
+        /// By default, this property is intiailized when <see cref="Controllers.IControllerActivator"/> activates
+        /// controllers.
+        /// <para>
+        /// This property can be accessed after the controller has been activated, for example, in a controller action
+        /// or by overriding <see cref="OnActionExecuting(ActionExecutingContext)"/>.
+        /// </para>
+        /// <para>
+        /// This property can be also accessed from within a unit test where it is initialized with
+        /// <see cref="EmptyModelMetadataProvider"/>.
+        /// </para>
         /// </remarks>
         [ViewDataDictionary]
         public ViewDataDictionary ViewData