 That night , Perry began work on another track , which she played for Stefani the next day to motivate her . Stefani was impressed with the track , and Perry asked her , " What are you waiting for ? " According to Perry , Stefani took the question as a dare , replying , " You 're totally challenging me , right ? " The two began writing lyrics for the new wave @-@ styled song based on Stefani 's writer 's block and fears about making a solo record , and it grew into " What You Waiting For ? " 
