Unprofitable? This joint succeeded, for one (9)
I believe the answer is:
thankless
'unprofitable?' is the definition.
(thesaurus)
'joint succeeded for one' is the wordplay.
I cannot really understand how this works, but
'joint' could be 'ankle' (joint of the body) and 'ankle' is present in the answer.
'succeeded' could be 's' (genealogical abbreviation) and 's' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
'this' is the link.
Can you help me to learn more?
(Other definitions for thankless that I've seen before include "Receiving no appreciation" , "Showing no gratitude" , "Unappreciated" .)