Analysis of information sources in references of the Wikipedia article "性兴奋" in Chinese language version.
Another difference has to do with how men react to instances when they can't become aroused. Males who are able to get aroused fairly easily seem unfazed by occasions where they can't get aroused. They tend to attribute it to benign external events--it was something they ate, or they're not getting enough sleep--not as characteristics of themselves. In contrast, men with arousal problems tend to do just the opposite, thinking of every instance of difficulty as a sign of a long-term internal problem, either physiological or psychological.
Another difference has to do with how men react to instances when they can't become aroused. Males who are able to get aroused fairly easily seem unfazed by occasions where they can't get aroused. They tend to attribute it to benign external events--it was something they ate, or they're not getting enough sleep--not as characteristics of themselves. In contrast, men with arousal problems tend to do just the opposite, thinking of every instance of difficulty as a sign of a long-term internal problem, either physiological or psychological.