(1/3) Almost everyone forgets that Steve didn't always looked the way he did, and that includes HYDRA, so one of the Soldier's missions was in a rather run-down building, his target a scientist who was persistent as hell in his search for certain cures that wouldn't benefit them at all, especially since the guy was SHIELD material through and through. They sent the Soldier, almost as an afterthought as part of a bigger hit, he got in and they heard the shot, but the Soldier wasn't coming out...
(2/3) the support team entered but what the saw definitely wasn’t what they expected, for there in the middle of the room curled around the body of the scientist (who was a skinny thing barely bones and skin, with blond hair matted with red and unseeing eyes) was the Soldier who was hugging him protectively while holding an inhaler to the man’s lips, whispering “don’t be a stubborn jerk, you are not fine, you are barely breathing… For me, take it for me… breathe… please?”
(3/3) It took the support team hours to get him to subdue, with him almost killing them everytime they attempted to take the body away. It took them years to understand what went down that day. Once they managed to see the photo of a pre-serum Steve they saw the resemblance between the victim and the disappeared war hero and as consequence took more severe measures with the mind-wiping to prevent this from happening again.
HOW CAN YOU DO THIS TO ME, I AM CRYING SO MUCH OH MY GOD