This is a psychological phenomenon where your performance is influenced positively or negatively by others' expectations of you. One example of this is in the classroom. A teacher tends to pay more attention and encourage students they like and expect to perform well. This in turn creates this positive feedback loop. From the student's point of view, they feel a need to prove them right and doesn't want to let their teachers down. This pushes them to work even harder resulting in a better performance, as expected. In a way this ends up being like a self-fulfilling prophecy. We can use this effect to positively affect the people around us. Hold high standards for the people around you and that will have an effect. Having higher standards for yourself can also lead to the same effect.
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