All could've been prevented

[Christmas]

You need to face the problem itself as SeeD.

Squall: Both Garden and SeeD were your ideas. Garden trains SeeDs.
SeeDs are trained to defeat the sorceress.

Zell: Yeah, and that Ultimecia! We can't let that sorceress from the
future mess up our world! Let's go kick her ass! We're SeeDs! We're
here to destroy the sorceress, right!!!?

Odine: There is only one way to defeat
Ultimecia. You must kill her in ze future.

Reflect on all those stuffs about destiny and fate throughout the game. This came along on how the idea of SeeD manage to come about and the reunion of the childhood friends. Not forgetting continuing a love story left unfinished by the earlier generations.