Taking so long makes this game no good! (4)
I believe the answer is:
solo
'taking so long makes this game no good' is the definition.
'solo' can be an answer for 'game' (I've seen this before). I'm unsure of the remainder of the definition.
'makes this game no good' is the wordplay.
'makes' becomes 'sol' (I can't justify this - if you can you should believe this answer much more).
'this game' becomes 'go' (go is a board game).
'no' is a deletion indicator.
'good' becomes 'g' (abbreviation).
'go' with 'g' removed is 'o'.
'sol'+'o'='SOLO'
Can you help me to learn more?
(Other definitions for solo that I've seen before include "Alone, unaccompanied" , "Aline in Oslo" , "Whist variant" , "Go it alone" , "Performed by a single voice or instrument" .)