diff --git a/java/test/org/broadinstitute/sting/WalkerTest.java b/java/test/org/broadinstitute/sting/WalkerTest.java
index 065013d4a..a718d2526 100755
--- a/java/test/org/broadinstitute/sting/WalkerTest.java
+++ b/java/test/org/broadinstitute/sting/WalkerTest.java
@@ -63,7 +63,7 @@ public class WalkerTest extends BaseTest {
             }
 
             System.out.println("Verifying on-the-fly index " + indexFile + " for test " + name + " using file " + resultFile);
-            Assert.assertTrue(IndexFactory.onDiskIndexEqualToNewlyCreatedIndex(resultFile, indexFile, new VCFCodec()));
+            Assert.assertTrue(IndexFactory.onDiskIndexEqualToNewlyCreatedIndex(resultFile, indexFile, new VCFCodec()), "Index on disk from indexing on the fly not equal to the index created after the run completed");
         }
     }