What are the opposite words for inefficient?

Efficiency is a critical aspect of modern life. It is the quality of being productive, effective, and proficient at something. Inefficient, therefore, is the opposite of being productive, effective, or proficient. There are several antonyms that can be used for the term inefficient, including productive, profitable, effective, successful, and efficient. Productive is being able to achieve a significant amount of work with less effort, while efficient is completing a job with less time, money, and energy. Effective is getting the job done with the desired result. In contrast, unsuccessful is failing to achieve the desired outcome, while unprofitable is a failed attempt to recover investments.

Antonym of the day

put together, twist, tangle.