diff --git a/src/Microsoft.AspNetCore.Localization/ApplicationBuilderExtensions.cs b/src/Microsoft.AspNetCore.Localization/ApplicationBuilderExtensions.cs
index 245ad7485d..47271237e2 100644
--- a/src/Microsoft.AspNetCore.Localization/ApplicationBuilderExtensions.cs
+++ b/src/Microsoft.AspNetCore.Localization/ApplicationBuilderExtensions.cs
@@ -105,7 +105,7 @@ namespace Microsoft.AspNetCore.Builder
 
             if (cultures.Length == 0)
             {
-                throw new ArgumentException(nameof(cultures));
+                throw new ArgumentException($"The {cultures} cannot be null.", nameof(cultures));
             }
 
             var options = new RequestLocalizationOptions()
diff --git a/src/Microsoft.AspNetCore.Localization/RequestLocalizationOptions.cs b/src/Microsoft.AspNetCore.Localization/RequestLocalizationOptions.cs
index ed49ce9006..16776364f0 100644
--- a/src/Microsoft.AspNetCore.Localization/RequestLocalizationOptions.cs
+++ b/src/Microsoft.AspNetCore.Localization/RequestLocalizationOptions.cs
@@ -110,7 +110,6 @@ namespace Microsoft.AspNetCore.Builder
         /// </summary>
         public IList<IRequestCultureProvider> RequestCultureProviders { get; set; }
 
-        
         /// <summary>
         /// Adds the set of the supported cultures by the application.
         /// </summary>
@@ -147,7 +146,7 @@ namespace Microsoft.AspNetCore.Builder
         }
 
         /// <summary>
-        /// Set the default culture to be used by the application when a supported culture could not be determined by
+        /// Set the default culture which is used by the application when a supported culture could not be determined by
         /// one of the configured <see cref="IRequestCultureProvider"/>s.
         /// </summary>
         /// <param name="defaultCulture">The default culture to be set.</param>