Leader in city, urban ecologist unfortunately just failing (5,3,2,5)

I believe the answer is:

close but no cigar

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'just failing' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'leader in city urban ecologist unfortunately' is the wordplay.
'leader in' says to take the initial letters.
'unfortunately' indicates an anagram.
The initial letter of 'city' is 'c'.
'urban'+'ecologist'='urbanecologist'
'urbanecologist' is an anagram of 'losebutnocigar'.
'c'+'losebutnocigar'='CLOSE BUT NO CIGAR'

Can you help me to learn more?

(Other definitions for close but no cigar that I've seen before include "It's not quite good enough" , "Very nearly" , "not good enough for Havana?" .)

I've seen this clue in The Telegraph.

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