Many a horsewoman experiences the frustration caused by a never ending, and never satisfied, expectation of perfection. It is common for performance horse riders to have high standards and expect nothing less than perfection from themselves and their horses.
In theory, that sounds like a good thing. Striving for perfection can help performance by being dedicated, by having a commitment to practice, by being focused and paying attention to the little details.
More commonly, however, perfectionism is perilous to performance. When a rider has placed so much pressure on themselves to perform perfectly, they become outcome focused. This leads to anxiety, and anxiety leads to not performing their best. When a perfectionist does not perform well, they tend to become extremely self-critical, leading to becoming overwhelmed and discouraged. This can lead to the rider wanting to quit, and not even try since they feel that they will not be able to perform at the perfect level they expect of themselves.