why do they make size 12 top with size 10 sleeves?

Question

I notices since I gone to the gym and lost weight around my waisted and strenght my shoulder chest muscle.
that shirts fit well except for the sleeves.

Answer 1

I think some women carry weight in their arms. You could have small hips and butt, but bigger arms. Just dont buy sleeves with the elastic. Looks like a rubberband around a piece of sausage, according to the "What not to wear" ladies.

Answer 2

that's because you've built muscle doing all the things to strengthen your chest and shoulders. you can't have one without the other. either get a bigger shirt or do weight exercises that are less arm-oriented