diff --git a/include/boost/iterator/iterator_adaptor.hpp b/include/boost/iterator/iterator_adaptor.hpp
index c72efbf..9c6cbfa 100644
--- a/include/boost/iterator/iterator_adaptor.hpp
+++ b/include/boost/iterator/iterator_adaptor.hpp
@@ -257,7 +257,7 @@ namespace iterators {
       {
           static_assert(
             std::is_convertible<my_traversal, random_access_traversal_tag>::value,
-            "Super iterator must have a random_access_traversal_tag."
+            "Iterator must support random access traversal."
           );
           m_iterator += n;
       }
@@ -268,7 +268,7 @@ namespace iterators {
       {
           static_assert(
             std::is_convertible<my_traversal, bidirectional_traversal_tag>::value,
-            "Super iterator must have a bidirectional_traversal_tag."
+            "Iterator must support bidirectional traversal."
           );
            --m_iterator;
       }
@@ -281,7 +281,7 @@ namespace iterators {
       {
           static_assert(
             std::is_convertible<my_traversal, random_access_traversal_tag>::value,
-            "Super iterator must have a random_access_traversal_tag."
+            "Super iterator must support random access traversal."
           );
           // Maybe readd with same_distance
           //           BOOST_STATIC_ASSERT(
diff --git a/include/boost/iterator/iterator_archetypes.hpp b/include/boost/iterator/iterator_archetypes.hpp
index 7c8e706..6696445 100644
--- a/include/boost/iterator/iterator_archetypes.hpp
+++ b/include/boost/iterator/iterator_archetypes.hpp
@@ -324,7 +324,7 @@ struct iterator_access_archetype_impl<
     template <class Value>
     struct archetype
     {
-        static_assert(!std::is_const<Value>::value, "Value type must be const.");
+        static_assert(!std::is_const<Value>::value, "Value type must not be const.");
         typedef void value_type;
         typedef void reference;
         typedef void pointer;
@@ -375,7 +375,7 @@ struct iterator_access_archetype_impl<archetypes::writable_lvalue_iterator_t>
             Value, archetypes::readable_lvalue_iterator_t
         >
     {
-        static_assert(!std::is_const<Value>::value, "Value type must be const.");
+        static_assert(!std::is_const<Value>::value, "Value type must not be const.");
     };
 };