The phrase "doest the job" implies a level of competency or effectiveness in completing a task. Antonyms for this phrase could include "inefficient," "inadequate," "unproductive," "unsuccessful," or "unsatisfactory." These words suggest that the task was not completed properly or did not meet expectations. Other antonyms could include "unreliable," "unfit," "useless," "worthless," or "unusable," indicating that the outcome of the task was not just subpar, but that it was a waste of time and effort. Alternatively, "overqualified" could be seen as an antonym, suggesting that the person or tool used to complete the task was too advanced for the job at hand.