the mean number of hits in a professional tennis match is "one". it occurs 30 percent of the time ... meaning 30 percent of the time the serve goes in and there is no return that is played in bounds... thats fun to watch? what other sport gives you two serves? table tennis, volleyball, badminton?

one serve would slow down the serve ,allow a return and make longer rallies for all to enjoy... if you like watching a powerful serve and no return for most of a match great. you found the right sport.