You could tell people you’re working on your elbow muscle and it’s getting huge! Lol Can you pull the sleeve down and straighten things out some? Leather is a natural material and will behave differently from garment to garment. Leather jackets seem to require a certain amount of acceptance and tolerance. Maybe more so than non leather materials. When some of us can’t accept the state of a jacket we seem to move it on and get another that’s more acceptable. Or just get another one. It’s a thing.