The antonyms for the word "were derelict" include being responsible, diligent, competent, capable, reliable, accountable, attentive, conscientious, faithful and dependable. A person who falls under these antonyms can be trusted to carry out their duties and responsibilities effectively, ensuring that nothing is left undone or unattended to. Being responsible means that one takes ownership of their actions and decisions, and can be relied upon to deliver desired results consistently. Diligence is the key to success, and those who are diligent in their work are likely to achieve their goals and objectives. Hence, the opposite of being derelict is to be diligent and committed to one's responsibilities.