Poor finish to the job at the end of the road (3)

I believe the answer is:

bad

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'poor' is the definition.
(similar in meaning)

I cannot understand how the remainder of the clue works.

(Other definitions for bad that I've seen before include "SECOND HALF OF 16" , "Mouldy, off" , "Substandard" , "Severe; of low standard" , "Rotten, evil" .)

I've seen this clue in the Evening Standard.

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