Some people (usually those who profit from jumps racing) would like us to believe that horses love to jump. Again, this is incorrect.
Horses only jump obstacles at full gallop because they are forced to do so.
Horses are intelligent animals with a high level of perception of their environment. If they approached an obstacle that required jumping over in the natural environment, the horse’s reaction would be to slow down, assess the obstacle and adjust their gait accordingly.
If you watch a show-jumping or eventing competition, you will see riders deliberately slow their horses as they approach an obstacle. This helps the horse to steady itself, to judge the height and to jump cleanly. Although there are still risks involved in these equestrian sports, they are far less than those experienced by a racehorse being forced by a whip-yielding jockey at flat gallop alongside other horses over obstacles.
Travelling at speed, these horses are not given sufficient time to assess the hurdle and can misjudge height and/or width, leading to falls. This ‘judgement’ is further compromised when many horses are jumping the same jump simultaneously.
Survival instincts mean that horses are unlikely to jump over obstacles at full speed and risk injury or death. Most horses that lose their riders during jumps races (which happens frequently) choose to run around hurdles and steeples where they can rather than to continue jumping.
(Compared to flat races, jumps races have a higher rate of horses failing to finish. Nearly 20% of starters fail to cross the finish line for a variety of reasons. Horses that do finish often struggle many tens of lengths after the winner and are never in contention. Sadly, this doesn’t stop many riders continuing to whip their horses even though they have no chance of success.)