High Expectations on Others
When we hold a high expectation on someone, we subconsciously want him to succeed, whether or not we are aware of it. This, in turn, causes the recipient to try to perform better to meet our high expectation. Psychologists call this "Rosenthal effect."
On the other hand, when we hold low expectations on someone, we unconsciously don't expect him to succeed. Although we don't necessarily tell him, the recipient notices our subliminal messages from our actions and subtle body language we project.
At school, when a teacher gives high expectations to a student, the teacher tends to encourage and speak to the student more often. As a result, that student becomes more engaged, asks more questions, and strives to become better. It goes without saying, the student has a higher chance of succeeding than his counterparts who are not expected to excel.
At home, if parents trust the ability of their son, they are not afraid to introduce intellectually challenging experiences to him, such as learning music or writing poems. In contrast, if they don't have any high expectations of the child, they will not think of giving him educational toys, for example, Lego Mindstorm. After all, they don't expect the child to be able to cope with learning programming.
High expectation on someones affects them subconsciously to perform better and meet the high expectation. It benefits both ways. While the receivers strive to become better to meet the high expectation, the givers are rewarded with high performance and respect as the receivers view them as a mentor or someone estimable.