diff --git a/doc-coverage/export-tests.rkt b/doc-coverage/export-tests.rkt
index ae411ab..8fe9fbe 100644
--- a/doc-coverage/export-tests.rkt
+++ b/doc-coverage/export-tests.rkt
@@ -8,11 +8,14 @@
          check-documented
          check-documentation-ratio)
 
+(define (fail-check-unless cond msg)
+  (unless cond (fail-check msg)))
+
 (define-check (check-all-documented module-name)
   (let* ([undocumented (module->undocumented-exported-names module-name)]
          [num-undocumented (length undocumented)])
-    (unless (zero? num-undocumented)
-      (fail-check (check-all-documented-message module-name num-undocumented undocumented)))))
+    (fail-check-unless (zero? num-undocumented)
+      (check-all-documented-message module-name num-undocumented undocumented))))
 
 (define (check-all-documented-message module-name num-undocumented undocumented)
   (string-append "Module "
@@ -29,8 +32,8 @@
          "Module foo has 8 undocumented bindings:\n\nfoo1\nfoo2\nfoo3"))
 
 (define-check (check-documented module-name binding)
-  (unless (has-docs? module-name binding)
-    (fail-check (check-documented-message module-name binding))))
+  (fail-check-unless (has-docs? module-name binding)
+    (check-documented-message module-name binding)))
 
 (define (check-documented-message module-name binding)
   (string-append "Module "
@@ -45,15 +48,8 @@
 
 (define-check (check-documentation-ratio module-name minimum-ratio)
   (let ([actual-ratio (module-documentation-ratio module-name)])
-    (unless (>= actual-ratio minimum-ratio)
-      (fail-check
-       (string-append "Module "
-                      (symbol->string module-name)
-                      " does not document at least "
-                      (number->string (exact->inexact (* 100 minimum-ratio)))
-                      "% of its bindings, only documents "
-                      (number->string (exact->inexact (* 100 actual-ratio)))
-                      "%")))))
+    (fail-check-unless (>= actual-ratio minimum-ratio)
+      (check-documentation-ratio-message module-name minimum-ratio actual-ratio))))
 
 (define (check-documentation-ratio-message module-name minimum-ratio actual-ratio)
   (string-append "Module "