What is a poor cut diamond?

Could you please explain what exactly is meant by a "poor cut diamond"? I'm curious to know if it simply refers to the shape or if there are other factors involved, such as the clarity, color, or the precision of the cutting process. Is it possible for a diamond to have a poor cut but still possess exceptional clarity and color? How does the quality of the cut affect the overall value and appearance of the diamond? I'm interested in learning more about the intricacies of diamond grading and how professionals in the industry determine the quality of a diamond's cut.