Failure of stylish chap finishing early (3)
I believe the answer is:
dud
'failure' is the definition.
(I know that dud is a type of failure)
'stylish chap finishing early' is the wordplay.
'stylish chap' becomes 'dude' (I've seen this before).
'finishing early' means to remove the last letter (the word finishes earlier than normal).
'dude' with its final letter removed is 'DUD'.
'of' is the link.
(Other definitions for dud that I've seen before include "Firework not going up" , "Inoperative" , "Phoney" , "A thing failing to work" , "Damp squib" .)