diff --git a/guix/channels.scm b/guix/channels.scm
index c2ea0e26ff..036c8d9b5d 100644
--- a/guix/channels.scm
+++ b/guix/channels.scm
@@ -369,10 +369,9 @@ commits ~a to ~a (~h new commits)...~%")
                                     #:keyring keyring
                                     #:report-progress report)))
 
-          (unless (null? commits)
-            (cache-authenticated-commit cache-key
-                                        (oid->string
-                                         (commit-id end-commit))))))))
+          (cache-authenticated-commit cache-key
+                                      (oid->string
+                                       (commit-id end-commit)))))))
 
 (define* (latest-channel-instance store channel
                                   #:key (patches %patches)
@@ -392,7 +391,8 @@ relation to STARTING-COMMIT when provided."
         ;; TODO: Warn for all the channels once the authentication interface
         ;; is public.
         (when (guix-channel? channel)
-          (warning (G_ "the code of channel '~a' cannot be authenticated~%")
+          (warning (G_ "channel '~a' lacks an introduction and \
+cannot be authenticated~%")
                    (channel-name channel))))
 
     (when (guix-channel? channel)