If you have to ask why or who needs 10 frames a second, then the answer won't mean anything to you. It was already explained by the surfer above, a full spin takes less than 1 second. Are 10 shots of it worth more to a sports photograper than 2 and a half? If your still saying no, then you have never seen or looked at those 10 frames shot in one second. I don't shoot surfers, but the same applies to shooting eagles in flight. They do some amazing things that 3, 5 or 6.5 frames just don't catch. If your able to catch it, your prints will sell and the 10 cent a dozen images of eagles flying along straight and level won't. 