...because I didn't spend all that time turning the Geth into sentient beings and convincing them to peacefully coexist with the Quarians and rebuild Rannoch only to go and wipe them all out. Nope, not gonna happen. I go synthesis every time. It ends the cycle once and for all, life in the galaxy ascends to its next stage of evolution, and everyone lives happily ever after. I think ya'll just can't get over the glowy green eyes.