Perhaps Austin's plant is not good enough (14)
I believe the answer is:
unsatisfactory
'not good enough' is the definition.
(I've seen this before)
'perhaps austin's plant' is the wordplay.
'perhaps' indicates an anagram.
'plant' becomes 'factory'.
'austins' is an anagram of 'unsatis'.
'unsatis'+'factory'='UNSATISFACTORY'
'is' acts as a link.
(Other definitions for unsatisfactory that I've seen before include "Poor" , "Not good enough" .)