In France, quietly left duck: it's a disaster (4)
I believe the answer is:
flop
'a disaster' is the definition.
(I've seen this in another clue)
'in france quietly left duck' is the wordplay.
'in' means one lot of letters goes inside another.
'france' becomes 'f'.
'quietly' becomes 'p' (p for piano and quiet).
'left' becomes 'l' (common abbreviation).
'duck' becomes 'o' (resembles zero - 'duck' in cricket).
'f'+'p'='fp'
'l'+'o'='lo'
'fp' going around 'lo' is 'FLOP'.
'it's' is the link.
(Other definitions for flop that I've seen before include "Fall clumsily, liked failed play" , "Fiasco" , "turkey" , "Complete failure" , "Total failure; fall heavily" .)