diff --git a/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultModelXmlFactory.java b/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultModelXmlFactory.java
index 7a5abd7d8235..7d713ea91a87 100644
--- a/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultModelXmlFactory.java
+++ b/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultModelXmlFactory.java
@@ -121,7 +121,7 @@ public void write(XmlWriterRequest<Model> request) throws XmlWriterException {
         Writer writer = request.getWriter();
         Function<Object, String> inputLocationFormatter = request.getInputLocationFormatter();
         if (writer == null && outputStream == null && path == null) {
-            throw new IllegalArgumentException("writer, outputStream or path must be non null");
+            throw new IllegalArgumentException("writer, output stream, or path must be non-null");
         }
         try {
             MavenStaxWriter w = new MavenStaxWriter();
diff --git a/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultPluginXmlFactory.java b/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultPluginXmlFactory.java
index dec67b0257b9..d1542caa178b 100644
--- a/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultPluginXmlFactory.java
+++ b/impl/maven-impl/src/main/java/org/apache/maven/impl/DefaultPluginXmlFactory.java
@@ -84,7 +84,7 @@ public void write(XmlWriterRequest<PluginDescriptor> request) throws XmlWriterEx
         OutputStream outputStream = request.getOutputStream();
         Writer writer = request.getWriter();
         if (writer == null && outputStream == null && path == null) {
-            throw new IllegalArgumentException("writer, outputStream or path must be non null");
+            throw new IllegalArgumentException("writer, output stream, or path must be non-null");
         }
         try {
             if (writer != null) {