Actually, Ye Mingyu's performance during the audition for the female lead role wasn't so bad, if Xiao Rufeng hadn't shown up that day, the director and the producer were both willing to give her the lead role. Unfortunately for Ye Mingyu, Xiao Rufeng not only delivered a stellar performance in her audition, but she also showed some of her martial arts skills, which Ye Mingyu didn't possess.
Because Su Xiaofei knew the scope of the series and what it was about, she had already prepared Xiao Rufeng for any possibilities before the audition took place. This gave enough time for Xiao Rufeng to work out and improve the condition of her body. Her punch was filled with power and her actions looked natural. This gave her an advantage over Ye Mingyu during their audition for the lead role.