“What you focus on grows.” — Esther Hicks
Our RAS (Reticular Activation System) is the filter that we observe the world through to prevent overstimulation. And since we are choosing to allow certain stimuli in, we then tend to think about those things (like a police officer seeing threats, or a poet seeing love inspirations) and as such we create a feedback loop that reinforces those thoughts.
That emo teen listening to morose music? It is self-perpetuating.
The child that loves to do math, that asks for more problems and races the checkout to add the groceries up and sees Fibonacci sequences and is fascinated by ratios? Probably going to do something mathematically based like science, engineering, or music because of their fascination becoming focus and then their mission.
Notice just the niggling little things your significant other does? By only seeing those, they will grow in magnitude and you are on a path to a broken relationship.
Notice the good. Feed your brain positive as opposed to negative thought and they will grow and bear sweeter fruit than the bitter ones of pessimistic origin.