Being badly led, sir, they do nothing (6)
I believe the answer is:
idlers
'they do nothing' is the definition.
(I've seen this in another clue)
'being badly led sir' is the wordplay.
'being badly' is an anagram indicator (letters in the wrong order).
'led'+'sir'='ledsir'
'ledsir' anagrammed gives 'IDLERS'.
(Other definitions for idlers that I've seen before include "Loafers, time wasters" , "They hang about doing nothing" , "They are disinclined to work" , "People who can work but don't" , "Loiterers, layabouts" .)