diff --git a/test/test-utilities.script b/test/test-utilities.script
index 9757f7dfc65bc97d18b76fb644fecf20dba645e3..ae9456ecbb86d6caff56d8e293e88cf538f0df14 100644
--- a/test/test-utilities.script
+++ b/test/test-utilities.script
@@ -247,7 +247,7 @@
 (delete-empty-directory (subpathname *build-directory* "deleteme/a/b/e/"))
 (assert (not (directory-exists-p (subpathname *build-directory* "deleteme/a/b/e/"))))
 (delete-directory-tree (subpathname *build-directory* "deleteme/")
-                       :validate (lambda (x) (and (<= 5 (length (pathname-directory x)))
+                       :validate (lambda (x) (and (<= 4 (length (pathname-directory x)))
                                                   (subpathp x *build-directory*))))
 (assert (not (directory-exists-p (subpathname *build-directory* "deleteme/a/b/c/"))))
 (assert (not (directory-exists-p (subpathname *build-directory* "deleteme/a/b/d/"))))