unsatisfactory

un|sat|is|fac|tory /'ʌnsætɪsf'æktəri/
[ADJ]
If you describe something as unsatisfactory, you mean that it is not as good as it should be, and cannot be considered acceptable.
The inspectors said just under a third of lessons were unsatisfactory...
He asked a few more questions, to which he received unsatisfactory answers.
= inadequate
≠ satisfactory