If you think turns are no big deal, think again. Horses don't come from their mothers with turns built in. They are trained to turn well. Poorly executed turns are probably the biggest reason for refusals, poorly jumped fences and knock downs.
Bad turns result in horses losing their balance, impulsion and, in many cases, their confidence.
In other words, bad turns create bad jumps and slow times. When a horse is in a turn, the outside stretches and lengthens and the inside shortens. This creates a need for the outside hind to step bigger in order to stay on the track of the curve. It is this lengthening and shortening that, over time, creates a horse that is capable of going straight forward with pace and scope, as well as balance. This, in turn, enables the rider to execute accurate turns at any given moment.