Why do trampolinists need good coordination?

Answer 1

They need to have good coordination in order to know when to kick out of more difficult moves involving multiple somersaults and twists. It becomes easier and your awareness increases the more you do the moves. You may land in the wrong position or wrong place if you have very bad coordination, I know from experience!

Answer 2

Because if you were looking at the ceiling and about to do a back handspring you would fall and probably brake something. That's why it's always good to see what's happening.