The beep drill only considers if the ball lands “in” or “out”. If the ball lands “in”, it continues throwing balls at an increased frequency until you miss 3 balls. If it lands out, it keeps track of how many have landed “out” and stops the drill after 3 misses. You can erase a miss if you get 2 balls “in”. This is impossible to do, however, if you are too tired, don’t have the desire or the footspeed to get to the ball. Hence the beep drill is primarily a footspeed, guts and cardio fitness test; not a groundstroke test. The Boomer beep drill is much better for tennis training than a simple shuttle run (suicide drill), or the standard “beep” test used by coaches worldwide because it is tennis specific. The distance you run is within the sidelines, not 20 meters (the distance a standard beep test runs). The standard beep test allows you to run straight ahead for 20 meters before reversing and running back. The Boomer beep test requires you to hit the ball at each reversal so you can’t just run straight ahead; you are forced to turn sideways (as late as possible) to hit the ball and learn how to do so efficiently, then reverse direction quickly so you have the best chance of reaching the next ball.