They told Leia Organa she would be a princess, so she watched her kingdom burn to ash in a permanent instant of pain. They told her she would be proper, so she ran away with a smuggler. They told her she would be a symbol, beautiful, to grace the battles' sidelines, so she positioned herself face-to-face with a Dark Lord, and refused to bend.
They told her she would be valuable; instead, she made herself indispensable.
A generation later, they tell Poe Dameron, child of the Resistance, that he'll surely be a pilot, so that's who he becomes. Before he can crawl, he falls asleep in his father's X-wing helmet. As his imagination grows, so do the space battles he enacts on his bedroom floor, plastic fighters warring over plastic systems, plastic planets, plastic people.
(Where Leia was made of glass, he'll someday realize he's made of plastic, too… something built on an assembly line, not born of sheer demand.)
They tell Poe Dameron he'll be unprecedented, so he shatters every flight record. They tell him he can fly anything, and he believes them, so he does. They tell him he'll change the world with the click of a trigger, and as he soars clear of Starkiller Base, the dream is so irrevocably real it makes tears spring to his eyes.
They tell him he'll be unforgettable; instead, he becomes dismissible, because it's a war that forges fighters, but a good fighter always ends the war.
Leia Organa was always unexpected – casting false presumptions aside with the ease of someone more closely bound to the future than the past, bound up in the very fabric of the Force.
Poe Dameron is presumed, puffed up, pretentious, built on public praise and renown – and when he trades his X-wing fighter helmet for a pillow that night, Starkiller's absence like a black hole in the stars, he isn't sure who he is without something to fight.