Conscientiousness is a desirable trait that refers to being diligent, responsible, and mindful in carrying out tasks. The opposite of conscientious is careless, reckless, and irresponsible. Therefore, the antonyms for the word "more unconscientious" could be -neither conscientious nor diligent-, -lazy-, -irresponsible-, -unreliable-, or -negligent-. These antonyms indicate a lack of responsibility, accountability, and focus, which could lead to poor outcomes, mistakes, and unfulfilled commitments. Therefore, it is important to strive for conscientiousness in all aspects of life, to be mindful of our actions, and take responsibility for their consequences.