From the article:
Conscientiousness, one of the Big Five personality traits, is defined as a tendency to control one’s impulses, be persistent, act dutifully, and live up to one’s obligations to others.
Conscientiousness has been linked to a variety of positive traits and behaviors, such as responsibility, dependability, hard work, goal orientation, self-control, and leadership. Some conscientious people, however, happen to be dogmatic, inflexible, unquestioningly obedient, and intolerant of uncertainty (i.e., they tend to see things in black-and-white).
On the other hand, if it had been two women who had both agreed that the one cup was the worst ever, it would have been a sure thing.