Our body structures are relatively symmetrical and are not made the same. The word here is ‘relatively’. Some of the ‘common anomalies’ (oxymoron huh?) are hunch back, long neck, lopsided shoulders, different length hands and/or legs, paunch, football thighs and calves. That’s on one side. On the other side,
So suits are made to either correct, hide, or balances something out for example lopsided shoulders and make it symmetrical. Or accentuate something for example creating a nice V-line effect with wide shoulders (to express masculinity).