elfeed-update-feed does not complete about elfeed HOT 3 CLOSED

What version of Emacs are you running? From the error message I'm guessing either your version doesn't have lexical scope (i.e. Emacs 23.4 and earlier) or you've copy-pasted tagger code (elfeed-make-tagger) to a separate file that's not using lexical scope (lexical-binding).

from elfeed.

Thank you, I was culprit of the latter. It worked well after I deleted this section of my.el file.
I copied elfeed-make-tagger function, as there was an undefined error while I was calling this snippet.

;; (add-hook 'elfeed-new-entry-hook
;;           (elfeed-make-tagger :feed-url "youtube\\.com"
;;                               :add '(youtube)))

• My version of Emacs is :
  GNU Emacs 24.3.1 (x86_64-apple-darwin, NS apple-appkit-1038.36) of 2013-03-13 on bob.porkrind.org
• Using elfeed
  elfeed-20141104.1857

from elfeed.

Hmmm, having that snippet in your config should work fine.
elfeed-make-tagger is defined using cl-defun in a lexically scoped file,
which is what sets up the missing feed-title variable. I wonder if your
cl-lib isn't compiled as it should be, causing some macro to be expanded
at the wrong time. Unfortunately macros don't play well with
lexical-binding, since they are expanded and compiled in the context of
the caller.

from elfeed.