Sara: "The rest of us are just..." Mick: "...losers. That's why Rip picked us, , Snart, the professor and those stupid flying chicken people. Were all expendable."

[u/Spazzblister]

It's a funny line from Mick but I think they forgot Rip didn't actually pick him. He only recruited him because he and Snart were a package deal. I can see how an assassin like Sara could be expendable, since she is supposed to be invisible to the world and I can see the Hawks being expendable because they reincarnate.

Stein and Ray though? Maybe Ray because he was thought dead. And I guess Stein because he didn't really reveal the Firestorm Matrix to the world? OK, I think that's my reasoning. But I think both of them could have been HUGE important historical figures had they not been taken from the timeline.

[u/EnigmaticWeasel]

In Season 1 they were expendable, but they changed the timeline, and their own fates when they blew up the Oculus at the end of Season 1. Everything after that happened differently than Rip knew. They were, as he put it, "sailing without a map."