Requirement none expected when being extremely selective (4)
I believe the answer is:
need
'requirement' is the definition.
(I know that need is a type of requirement)
'none expected when being extremely selective' is the wordplay.
I cannot really see how this works, but
'when' could be 'e' (I've seen this in other clues) and 'e' is found in the answer.
The remaining letters 'ned' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for need that I've seen before include "''A friend in .... is a friend indeed''" , "must have results!" , "'miss'" , "Rely on" , "destitute state" .)