Discussion

Very broadly, yes.

Different people have different natural metabolisms, different builds, propensity toward muscularity, bodies that store fat in different areas and at different rates.

Of course, diet and physical activity play into this heavily as well, as does age.

A lot of people will be naturally skinny and more active when they are young, then you add a decade of sedentary office work... and they've never needed to learn how to eat well and exercise enough... and they get larger.

Other people can start off larger, learn a whole lot about healthy diet and exercise, and go in the opposite direction and become much more fit in that same decade.