There are several causes for downed poles during this event.
1) Pole bending requires a level of precision unmatched by any other timed rodeo event. Many riders underestimate the skill required at high speeds and invariably knock the poles down.
2) Horses often stiffen when rounding poles. A horse that flexes at the wrong time can position the rider too close to the pole, causing the rider to down the pole with her knee.
3) Direction changes require perfect timing. If a horse changes direction a second too soon, the rider's knee will often down a pole.
4) A horse that flexes in the wrong direction can cause downed poles. Ideally, a horse should flex in an arc that surrounds the pole. When the horse is inversely flexed, its flank can push the rider's knee into the pole.
In Pole Bending, it is important to bend your horse. Getting the horse to flex around the pole creates more clean pole runs.