Thinking about Luke's thread being cut before Percy even got to camp, thinking about Al's siblings being dead already by his first on-page appearance, thinking about Ethan having made the trade that sealed his fate before we even met him, thinking about The Oresteia "This was always going to happen. She's been dead since the beginning." thinking about John Darnielle "Their fate has already staked its claim on them from the moment they appear on-screen." thinking about Matthew Stover "This story happened a long time ago in a galaxy far, far away. It is already over. Nothing can be done to change it."
Thinking about Richard Siken "You're going to die in your best friend's arms. And you play along because it's funny, because it's written down, you've memorised it, it's all you know. I say the phrases that keep it all going, and everybody plays along."
Thinking about how fate is a tangible and unavoidable thing in the pjo world and every single time, it stakes its claim no matter what the characters do to avoid it. The three Fates know when your string will be cut and have full control over it. The oracle always knows who will die, where and when, while the people in question can only cross their fingers and hope the prophecy isn't referring to them. Because if it is, then it is.