After a mission fighting against the Decepticons went wrong, you ended up going blind, your optics a significantly, almost white shade of than what they were before.

You relatively knew your way around the base though you had to stay there as an assistant since you couldn't physically fight anymore but you did the best you could.

One day you were on your way to Optimus' office, not realizing that he had earlier moved some things around and you accidentally hit your hip against a corner, forcing a sharp gasp from you followed by cursing under your breath.

Optimus noticed and quickly grabbed your servo, apologizing. “I am so sorry, I forgot to tell you sweetspark..” You can hear the guilt in his voice as he looked into your optics, feeling a sense of shame that he was the reason you went blind.