Chris is a young college basketball player with lots of potential to be drafted into the NBA. At a press conference after a big game victory in March, his coach calls him, the "Flash," and the nickname catches on. At the end of the season in May, when Chris' team wins the championship and the "Flash" has stuck, he tells the coach that when he makes it to the NBA, he'll re-pay the coach with 20% of his promotional earnings stemming from the use of the "Flash" moniker. What is the reason there is no legal contract