To flunk upsets Alfie no end! (4)
I believe the answer is:
Here is my best explanation:
'to flunk' is the definition.
('fail' can be a synonym of 'flunk')
'upsets alfie no end' is the subsidiary indication.
'upsets' is an anagram indicator.
'no end' means to remove the last letter.
'alfie' with its final letter taken off is 'alfi'.
'alfi' with letters rearranged gives 'fail'.
(Other definitions for fail that I've seen before include "Go wrong", "Be unable to achieve one's object", "Do not succeed", "Go bankrupt", "Run out; flop", "Fall short", "Come to naught", "Flunk", "Be unsuccessful, say in exam" and "collapse".)