Crude depiction's thus a failure (15)
I believe the answer is:
unsophisticated
'crude' is the definition.
(I've seen this before)
'depiction's thus a failure' is the wordplay.
'failure' indicates anagramming the letters.
'depictions'+'thus'+'a'='depictionsthusa'
'depictionsthusa' is an anagram of 'UNSOPHISTICATED'.
(Other definitions for unsophisticated that I've seen before include "crude" , "Simple" , "green" , "Lacking experience" , "straightforward" .)